Application of Transparent Ink in Printing and Troubleshooting 1

With the continuous improvement of packaging requirements, packaging design and printing have become more diversified. Printing colors in the packaging and printing of products is always the focus that attracts people's attention. For example, most of the outer packagings of goods in shopping malls have high transparency and give people a feeling of glitter. To this end, a variety of special inks have been developed and widely used in pearlescent inks, etched metal inks, coral inks, fluorescent inks, ice inks, and the like. The application of special inks has not only enhanced the artistic effects of packaging and packaging, but has also increased the security of persuasiveness to a certain extent. The application of clear ink in packaging printing (mainly in high-grade flexible packaging such as flexible packaging, such as food industry) also adds color to packaging printing. It occupies a special position in packaging printing. Transparent ink is used for aluminum or aluminum foil printing. For the best visual effects. Nowadays, transparent ink has been widely used in the packaging and printing industry for specific applications such as flexible packaging in the food industry, carton packaging in the brewing industry, and carton packaging in the tobacco industry. Let's talk about the application of transparent ink in packaging printing.

Transparent ink features

Transparent ink refers to all or most of the colorants using high-grade transparent pigment (dye) binders. High-grade transparent resins as the main raw material, together with other types of additives, are finely ground inks. Their hiding power is very low. . Transparent ink can be divided into table printing transparent ink and in India (composite) transparent ink. Although the transparent inks of both the table and the printed inks belong to the same type of inks, they are generally not to be mixed. In particular, the transparent inks of different brands produced by different manufacturers cannot be mixed to avoid failure and quality problems. Compared with other types of inks, transparent inks have the characteristics of high drilling degree, high transparency, high brightness, bright colors, strong adhesion and strong coloring power. In addition, the leveling property of the transparent ink is generally better, and almost no problems such as knife lines occur during printing. The fineness of the clear ink is generally less than 10 microns, so its hiding power and transferability are better than those of other inks, but the transparent ink of the table printing is not as good as the high temperature resistance of the transparent ink printed in India. In the design of packaging bags generally have less transparent ink in the heat sealing knife at the place of the phenomenon, the table printing transparent ink generally high temperature around 20 °C, of ​​course, some ink manufacturers have produced a more transparent high temperature resistant ink. The transparency of clear inks is determined by pigments, binders, and auxiliaries and the former plays a major role. The latter has little effect. For the inks made of common resins such as polynitrogen acetal, polyamidamide, and nitridation polypropylene, the transparency of the azoic ink is high. In general, inks with dyes as colorants have higher transparency than those with pigments as colorants. Sometimes due to other aspects of the rare, but also in the dye mix some of the pigment at this time the transparency of the ink will be reduced. The dyes used in clear inks are completely soluble in organic solvents so when the print comes in contact with the compounding adhesive. The solvent in the adhesive will dissolve the transparent ink on the print more or less. Although increasing the speed of recombination or improving the adhesiveness of the adhesive can alleviate this problem to a certain extent, it is not a fundamental solution. In addition, some pigments can be added to the dye to make transparent inks. This also has some improvement in the problem of dissolution of clear inks, but the transparency will be reduced. In response to this problem, some ink factories have developed transparent inks that are completely insoluble in alcohol-soluble gelling agents and have been applied to certain printing materials. Therefore, the development of a transparent ink that is insoluble in vinegar-soluble adhesives is the fundamental solution to the problem.

In packaging printing, transparent inks are mostly printed with composite aluminized films. However, many transparent ink-printed products often suffer from poor peel strength when composite aluminized films are used. In fact, this is also a problem with other inks. For example, when printing with other inks, if the white ink substrate is not printed on the composite aluminum film (especially VMCPP), the peel strength may be poor, but it is usually printed with other inks. This process is rarely used, so poor peel strength is rarely observed. Due to the high transparency of the transparent ink, the gloss of the aluminum film and the gloss of the ink are generally combined after printing to reflect more vivid colors. Moreover, products printed with clear ink will have more noticeable changes in the viewing of the hue from different angles. Differences observed under different light sources will be even greater. Therefore, in the deployment of transparent ink must understand what customers composite materials in order to deploy the same process and the ink in a similar environment to observe the hue of the ink.