Talking about the Advantages of Cationic Ink in Printing Process

In recent years, photocuring UV technology in flexographic printing has played an important role in the printing of paper and film materials. UV technology has moved from narrow web flexography to the flexographic printing market. In offset printing, we also saw the advantages of the UV ink quick drying system, which can shorten the printing cycle and reduce the workload. The most important feature of UV curing system is that it can improve printing stability (drying aspect) and shorten the waiting time of oxidative drying in the printing process. In the past 10 years, UV printing has had a great impact on the traditional, mainly on the plastic substrate flexographic printing.

Now there are new types of cationic inks. It increases the environmental protection and quality of flexographic printing and increases its guarantee. Compared with the free ink system, the cationic ink has the advantages of low volatility and small odor. It is a very good environment ink. The odor of free radical inks is a big headache and it is harmful to the health of operators and the environment. The cationic ink (low-volatile ink) has a great advantage in this regard, and it can even be applied to some food packaging industries. The cationic ink has the advantage of being attached to a plastic substrate. Cationic inks and coating gloss show good adhesion to corona-treated substrates. This is the most critical of all the advantages.

Cationic inks have a moderate cure speed compared to free radical inks (which is slightly inferior to free radical inks, can be re-cured (approx. prolonged to 24 hours), does not prevent oxidation, has minimal moisture effects, no shrinkage, and excellent plastic adhesion Features.

Although the curable speed, the free radical type ink can be dried under high speed printing, and the curing speed of the cationic ink is slightly behind. However, recent research and development shows that the improved cationic ink can also adapt to 150-200m/min printing.

The benefit of the secondary cure is that the ink film appears to have cured after the print has been output from the printer, but there is still some reaction (not dried). Cationic curing technology can continue to react until most of these materials react.

In contrast, radical inks can only be exposed to UV light for thorough drying. This process in turn leads to higher volatilization, especially low-molecular-weight components that are unreactive, more volatile, and the volatilization of volatiles is also reflected in the extractable components. The content of extractables is an increasingly important feature of testing food packaging systems. In particular, as an analytical technique, the content of the extractable component is one part per billion, and even an amount of one trillion parts is now being discussed as an indicator of the content of the packaged product. Cationic inks have a small amount of shrinkage and therefore have good adhesion characteristics.