Application Characteristics and Development of Mixed Ink

Hybrid Ink is a new type of ink formulated by mixing ordinary ink components with UV curing materials. It combines general ink and UV curing technology. One or more UV curing lamps are installed on the printing machine to make the ink energy. Printing on traditional sheetfed presses allows UV Varnish to be quickly printed on a blended ink and cured for a uniform, high-gloss finish. Mixed inks perform less well than standard UV inks, but hybrid printers are a good choice for printers who want to make less money.

As early as the last century, UV Varnish has become the first choice for coating with its high gloss, instant drying and good abrasion resistance. However, the chemical composition and chemical properties of UV Varnish and common ink are quite different. , The incompatibility between the two leads to poor adhesion between ordinary inks and varnish. In addition, the initial high gloss of printed gloss finishes does not last long after printing, resulting in a decrease in gloss, resulting in a non-uniform gloss of the printed product, and a large dark area with a large ink coverage area with the largest degree of gloss reduction, while the coverage Areas with small areas or no printing ink are still bright. If ordinary inks are completely dry before they are applied, the UV coating effect is very good. Ordinary ink to prevent back-scratching during the drying stage, it is necessary to spray powder, dusting will make the surface of the light should be smooth and smooth sand appearance, affecting the glazing after printing the appearance of beautiful. Afterwards, the use of water-based varnishes on the glazing and minimizing dusting had a better effect. However, the printed sheets must be fed twice in the printing press, which increases the cost and reduces the efficiency. In order to overcome this shortcoming, printing machinery manufacturers developed a printing press with double coating units. When the paper is fed at once in the printer, the two coating units print two coats of plain lacquer on the common ink. First, a layer of water-based polish was applied to cover the normal ink layer, and then printed with UV polish to give it a high gloss. Since waterborne varnish is difficult to fully dry, the true drying of the aqueous varnish requires the coalescence of the acrylic emulsion in the varnish. To accelerate its drying on the press will inevitably cause Other problems.

Although some prints are very good with this type of glazing, they are still difficult for a wide variety of prints. In recent years, some ink manufacturers have developed common ink materials and curing materials, and put UV lamps on the front of the UV polishing unit to dry the mixed ink. After the UV coating, a high gloss is formed on the surface of the printed matter. Mixed inks. It is a kind of mixed ink that combines common materials with UV-curable materials. When used, the UV ink at the end of the printing unit and the UV coating unit can completely cure the mixed ink. The specific glazing effect depends on the type of UV varnish, substrate, and glazing device used, but when the blended ink is combined with the UV varnish and cured very well, a print that is uniform in gloss and bright is obtained. The characteristics of mixed ink Compared with ordinary ink, mixed ink has many advantages: mixed ink printing combines the characteristics of UV light curing and traditional offset materials, so that the ink can be UV light cured to maximize the characteristics of UV ink. The key to this process is UV-curing technology, where high-energy UV lamps cure and dry mixed inks instantly between the press and the coating unit. This instant cure dramatically reduces energy consumption, reduces production, storage, and disposal costs and increases production efficiency. Mixed inks do not require the use of UV. The inks used are special ink rollers, blankets, and fountain solutions. In this way, printers use mixed inks when they need to be glazing on line, printing them with ordinary inks without glazing. In the case of mixed inks and ordinary inks, different ink rollers and blankets may have some effects when used with mixed inks. Printed with mixed ink, the gloss after UV coating will not fade, it is especially suitable for high hiding power of ink.

The printing performance of the mixed ink on the printing press is also like ordinary ink. UV ink ink balance is generally more difficult to control, but the mixed ink is similar to ordinary ink, control the ink balance is not difficult. The printing characteristics of UV inks, such as dot gain, overprinting, and printing contrast, are inferior to ordinary inks, and mixed inks are similar to ordinary inks. In addition, because the UV curable material in the mixed ink is not dried before the UV lamp is irradiated, the mixed ink is always flowing on the printing machine, so the printing failure is not caused by the crusting on the ink roller like the ordinary ink. Because of the instant drying achieved by printing with a mixture of inks, it is possible to apply UV glazing on the press without the need for water-based varnishes. The print quality is no worse than ordinary offset inks. Mixed inks have a wide range of adaptation and low investment. For printers that already have UV technology, they only need to purchase a mixture of inks. For printers that do not use UV technology, they only need to invest in UV curing equipment and UV lamps in addition to purchasing mixed inks. In addition to being used primarily for paper printing, hybrid inks can also be used in non-absorbent printing materials such as plastics, aluminum foil, and metal paper. It has good adhesion to plastics. Utilize UV ​​curing technology to solve the ink drying problem of non-absorbent printing materials. The mixed ink prints clear dots and improves the quality of offset printing. Mixed inks can be used on sheetfed presses as well as on narrow web presses. More and more mixed inks are now being used to print products that require good gloss, such as photo albums, posters, cards, folding cartons, pharmaceuticals, and cosmetic packaging boxes.

When printing with mixed inks, it is important to note that at least one UV lamp is installed behind the last printing unit and before the UV coating unit. According to the speed of the printing machine and the hiding power of the ink, an additional UV lamp can be added to prevent the ink from drying out completely. A glazing device is also needed, and a certain number of UV lamps are installed at the rear of the printing machine to ensure that At the printing speed, UV coating can be fully cured. There are many possibilities for the configuration of the printing press. The most typical is to install a UV lamp before and after the coating machine. Although it is generally not required to use lamps in the printing units, there are also manufacturers who have found some advantages in installing UV lamps in the printing units. Mixed inks can also be glazed with waterborne coatings.

Some printing companies have found that such processes improve the surface gloss of prints. Although the coating effect is inferior to the UV coating, it is better than using an aqueous coating on ordinary inks. The biggest deficiency of current mixed inks is that they are more expensive than regular offset inks. However, the use of mixed ink printing can instantly dry, save labor, reduce scrap, and speed up preparation for printing, so the overall cost does not increase. At the same time, it can be shipped immediately after printing, which increases productivity, reduces dusting and related maintenance costs. Another area of ​​improvement for hybrid inks is that when high-gloss products are printed with multi-colored inks, the technology has not yet reached perfection. The future of mixed inks will be a new direction for the development of ink technology. Future hybrid inks will be developed in several directions: development of high-efficiency UV curing technology for mixed-ink printing, and color mixing inks that are inexpensive, have high gloss, and have no deterioration in gloss are also an important development direction.