Editor's Note: Previously, we have plastic film on the offset, the main use is based on mineral oil is expected to connect. However, with the printing plant, plant products and end-user performance requirements for the improvement of ink, UV ink gradually replace oil-based ink. In this paper, we will be both the status of the ink system and technology innovation in detail.

Currently, synthetic materials such as plastic film and other non-absorbent substrates in the printing areas, especially in the field of offset printing are becoming more and more frequent use. And we want for these applications to find a suitable printing ink system, it is necessary to make the system have the following characteristics:

1. Printability good;

2. In the high-speed printing presses run better on the properties;

3. In the non-absorbent substrates on the adhesion and scratch resistance of.

Paper and cardboard with the majority of different substrates, the plastic film surface structure does not allow the infiltration of ink, not so fast-drying ink. In addition, the use of offset the dampening solution to the oil-based ink will be the impact of the drying process. Therefore, a good balance is the impact of the ink drying process, a key factor. To this end, it is specially developed for the synthesis of substrates of the oil-based inks, it is not only able to meet the specific technical requirements, and can guarantee the quality of printing products. However, fast-drying, safe stacking, adhesion and abrasion resistance, such as a compromise between the performance of oil-based ink is still currently facing a problem.

And the characteristics of UV curing technology just to make up for oil-based ink in the above-mentioned shortcomings of the issue: it's the Mexican film curing time, almost from the dampening impact of the number of fluid, and fast to prepare for follow-up processing.

UV-curable ink upgrade

When the UV ink system was first introduced in the printing industry, it is often due to poor performance on the offset press and the issue of adhesion has been questioned. But now, through an improved ink formulation and adoption of new raw materials, has been successful in eliminating the traditional UV ink defects exist.

UV ink Printability

For plastic film and other non-absorbent substrates, the dampening fluid can not penetrate into the surface of substrates, therefore, the first generation of UV inks is very easy to pile up in the drum, the printing plate and blanket, which lead to serious quality problems. At this time, we need to rely on the ideal balance of the ink to improve the printability of the ink. A new generation of UV inks have a greater ability to absorb, but also for the Solution provides greater useless.

In recent years, non-alcoholic printing out a growing trend of development, especially in the film and foil printing, isopropyl alcohol (the alcohol) has become an ideal choice for people, it can by reducing the surface of Solution tension to optimize the printing process, so that the printing ink system achieve the desired balance. In addition, people also can use other alternatives to alcohol wetting and printing plates, such as unit.

UV ink adhesion

The past, UV ink attached to the metal foil is difficult and the film surface, and now these problems have been through the development and optimization of a special group of ink formulations have been effectively resolved.

However, the use of UV inks and a pre-condition such as PVC substrates can not contain plasticizers, static inhibitors and other ingredients to reduce ink adhesion.

PVC surface tension can be maintained in the best 35mN / m or so, for the use of ABS, PP, PET, PE and PS materials, such as substrates, the surface tension should reach at least 40mN / m or more. In addition, these substrates should not be contained in static inhibitors, such as additives, so as not to hinder their team's uniform distribution of ink adhesion. Synthetic material of the surface tension of the formulation depends mainly on the material and manufacturer. Ink manufacturers will sometimes point corona discharge technology to deal with the surface film. With the extension of storage time, the surface tension of substrates will be decreased, and the corona discharge pre-treatment must be directly in the web or sheet-repeated presses on. Of course, this approach also applies to pre-treatment without the substrates.

UV-curable ink film flexibility

UV ink and coating be easily contracted in the curing process. Ink film or coating thicker, they will be the greater the shrinkage. Such an outcome is the result in a decline in ink adhesion. Ink adhesion and high flexibility ink, paint and materials used to connect directly related, because they help to reduce the degree of contraction of the ink.

UV curing ink

On the curing characteristics of different ink / coating impact adhesion. If you can not be completely curable ink, which is bound to receive the weakened adhesion. In a few cases, too dry ink / coating layer also may be a serious contraction of the phenomenon and, ultimately, flexibility and flexibility resulted in the decline.

UV ink functionality

In the early development of UV technology, it is almost impossible to use them in films and printed on metal foil. Today, improvements in quality and performance so that we can more on paper substrates printed UV film.

The requirements of the UV system

Cold UV system can reduce emissions of heat production and paper stack temperature, and placed the metal foil film and the deformation. But it will also slow down the UV ink and coating speed of polymerization. If the reaction process in the ink by adding nitrogen, the cross-linked polymer cells will accelerate the pace and bring us a higher production rate. For every printed piece of living, we have to ink and coating adhesion test. And of different scratch-resistant, the ink adhesion is generally not in the print within 12 hours after the occurrence of change much.

Summary

As consumers can choose from the substrates of the constantly expanding range of options - from plastic films to metal substrates, ink manufacturers are continually improving their products. In addition, the printing speed and reduce the drying time also we launched a serious challenge.

As the case successfully resolved the problem of shrinking, so oil-based ink will be applied in many specific areas, however, UV inks are also not to be outdone, it will improve the formula adopted to strengthen the pre-press phase of the color control and drying equipment objects characteristics continue to expand its market in the printing area.