Interview: "LED UV curing system is the technology of the future"

Siegwerk developers have successfully developed UV/LED offset ink systems with good de-inking performance. In our interview, Thomas Glaser, head of Siegwerk's Sheetfed EMEA technology business unit, talked about the features, advantages and disadvantages of the new ink system.
de-inking process is the most important part of processing waste paper

. So far, however, UV curing inks have rarely met the criteria for good recycling balance. Why is that?
Glasser: UV/LED UV inks form solid, chemical and mechanical resistance layers after curing, comparable to adhesive plastic layers. Although this strong attachment of inks and paper fibers leads to a preferred high stability of the ink film, it also complicates the removal of inks during recycling. Until now, the crosslinking ink particles of standard UV/LED UV inks have not been sufficiently removed from paper fiber blocks, often leaving large stains on recycled paper as colored spots visible to the naked eye, thereby reducing whiteness. Regenerate the pulp to regenerate the quality of the paper.
you have now developed a UV/LED UV offset ink system with good de-inking performance. Where do you concentrate?
Thomas Glaser, head of Theheetfed EMEA's technology business unit at Siefwerk
Glaser: Our goal in the development process was to develop an ink system that clearly de-inks, or in other words, removes from various types of paper. To identify and evaluate de-inkability, we use the internationally recognized test standard INGEDE method 11 and the EPRC scorecard. So far, three independent agencies have confirmed the good de-inking performance of the new ink system. In addition, we aim to gain a wide range of knowledge about the future. We wanted to see what needed to be done to adjust the UV/LED UV curing ink/varnish layer so that it was fragmented enough and effectively removed from the paper fiber pulp in the flotation slot.
is special about the new ink system?
Glasser: In addition to providing good de-inking performance, the new Sicura Low NRGY UV/LED UV series offers excellent printability. In addition to considerable printing stability and high gloss, the user also confirms convincing point clarity and excellent fluidity, as well as rapid curing and good mechanical strength.
what type of paper does your new development apply to? Does it only apply to newspaper printing or packaging printing?
: For de-inking, the main use of drawings, not cardboard packaging. For our research project, we examined the de-inkability of different types of paper. The new ink system has achieved the overall effect of "good de-inking" on wood-free coated paper, native fiber modified news paper and coating machinery, and recycled paper. Today, our newly developed UV/LED UV inks are primarily used for commercial use. Print.
the shortcomings of the new ink system and what else needs to be realloced?
: Many users in Europe have already used the new ink series on different presses with great success. "Sicura Low NRGY UV / LED UV" has even proven to be ideal for non-alcoholic printing. So far, there are no shortcomings to address.
are the difficulties of paper recycling?
: In de-inking plants, high concentrations of non-de-inkable materials can cause serious problems with dirt particles, resulting in waste and significant economic losses. Each individual printed product that is difficult to de-ink means that the cost of de-inking equipment is high and the huge additional costs in the manufacture of de-ink paste to achieve the target values for whiteness and other quality parameters.
new applications for new ink systems?
Glaser: As part of our research project with Stora Enso, we are able to demonstrate that the new ink system has good de-inking properties, standard UV, LED UV and iron doped UV curing, such as LE-UV, H-UV, HR-UV and LEC-UV. As a result, "Sicura Low NRGY UV / LED UV" is typically used in any UV/LED UV commercial press.
is the demand for UV cured inks? How do you think it will develop?
: Demand for UV curing inks remains high, especially as LED UV curing systems are the technology of the future.