Sunchem introduced the thermochromic ink for shrink film in June of this year. The ink is designed for shrink film packaging and printing, and is very suitable for the following product packaging applications: yogurt, dairy products, cold drinks and children's dairy snacks, which come from The commercial tests conducted jointly by three cold drink manufacturers in Germany, the United Kingdom and the United States are environmental protection inks. The company also said that in the next three years, it will continue to develop and develop other types of thermochromic inks for special applications.

With the rising demand for environmental protection, ink as the main component of printing, its environmental protection requirements are also increasing. The problem of air pollution caused by the volatilization of solvents in the ink is the most serious with gravure ink, because it uses more VOC as a solvent. Long-term exposure to high concentrations of VOCs will cause significant damage to the human body, especially the nervous system. VOCs will also react photochemically with nitrogen oxides in the air to produce ozone and fumes, causing atmospheric pollution. To reduce VOCs, there are two solutions for recovering and burning the discharged solvent, but many gravure machines are not equipped with such devices. In addition, the discharge of water-based cleaning ink and offset fountain solution can contaminate the water quality. The disposal of industrial waste such as printed materials and ink containers is also very tricky.

Therefore, it is imperative to research and develop gravure printing inks with environmental protection requirements. The so-called compliance with environmental protection requirements is to change the ink composition and use environmentally friendly materials to formulate new inks.

Benzene-free solvent inks and water-based inks

The fundamental difference between water-based inks and solvent-based inks is that water-based inks use water as the solvent instead of organic solvent, which significantly reduces VOC emissions, prevents air pollution, does not affect human health, is not easy to burn, and is stable in ink, colorful, and does not corrode. Plate material, simple operation, low price, good adhesion after printing, strong water resistance, rapid drying, it is especially suitable for food, beverages, pharmaceuticals and other packaging printed matter, is the world recognized environmental protection printing material, is also the current all printing ink The only ink approved by the U.S. Food and Drug Association. At present, 40% of U.S. plastic printing uses water-based ink, and other economically developed countries (such as Japan, Germany, France, etc.) use more water-based ink in plastic film printing. In June this year, the United Kingdom enacted legislation to prohibit the printing of food films using solvent-based inks. According to relevant data, in the United States, water-based inks complying with the VOC regulations must reach the state of use of the ink composition, the proportion of volatile components is below 25%, the moisture content is above 75%, and the water with less moisture is in use, the non-volatile components are used. Above 60% of these two standards. Water-based inks are usually used for printing paper products including paper-plastic composite products. The characteristics are to meet the ink absorption of paper printing, so that the prints are full-colored, and even more rare is that the solvent is water and ethanol, and the environmental pollution is small, and it is an environmentally friendly green ink.

At present, there are still many companies that use gravure printing inks that are generally made of chlorinated polymers. In the ink production process, the chlorinated polymer needs to be dissolved using a strong solvent (such as toluene and other aromatic solvents), and the viscosity of the ink needs to be adjusted during the printing process using toluene. Chlorinated polymer ink systems are now considered unsuitable for environmental protection. This is because the chlorofluorocarbons that are volatilized during production can damage the ozone layer. The use of aromatic solvents (toluene) can cause injury to the health and safety of workers during ink production and printing. In addition, the solvent residue in the packaging ink is another important issue to pay attention to. Since toluene is a slow-drying solvent, it easily remains in the dried ink film layer, corrupting the food in the package and causing harmful odors.

The production of plastic gravure inks is under the control of fire laws, labor safety laws, and health laws and regulations. Therefore, it is an inevitable trend to actively develop and apply green gravure inks and water-based inks that meet environmental protection requirements. Film packaging material gravure waterborne.

Although water-based gravure inks have attracted much attention as an alternative to toluene-based inks, the inks in packaging film printing are still water-based and have not yet reached a truly practical stage. On the whole, the important reason why water-based gravure inks have not been popularized further is that the printing performance and quality are still not up to the standard for solvent-based gravure inks. This is mainly due to the higher surface tension of water, which makes it difficult for the ink to wet. If the printing speed and printing quality of the gravure solvent ink are to be obtained, not only the aqueous ink itself requires advanced technology, but also the gravure printing apparatus and the printing plate roller need to be improved. For example, changing a corrugated or engraved drum with a groove depth of approximately 38-42 micrometers to a laser-made plate roll with a groove depth of approximately 24-28 micrometers also requires more effective and powerful drying equipment and printing that must be manufactured using corrosion-resistant materials. Roller, ink pump and scraper components. These improvements require considerable investment.

Gravure alcohol-soluble composite plastic ink

Since water-based gravure inks are not yet fully capable of replacing toluene inks, the ink industry has been working hard to develop alcohol-soluble inks that can be accepted by the environment. Alcohol-soluble ink can effectively solve the health problems caused by toluene ink and solvent residue affect the quality of packaged food and other issues. In Europe and the United States, this development has become a trend. In Asia, such as Singapore, South Korea and other countries, toluene ink is being eliminated, will be replaced by alcohol-soluble gravure ink. Alcohol-soluble inks are now widely used in the domestic gravure printing industry. It can be predicted that in the near future, alcohol-soluble inks will occupy a major share of the high-grade food and pharmaceutical flexible packaging ink market in China.

The gravure alcohol-soluble composite plastic ink has the characteristics of low odor, benzene-free, and the use of such environmentally-friendly inks will certainly increase the competitiveness of gravure printing in the field of packaging printing.

The development trend of the traditional Asia-Pacific ink to the environment-friendly ink

Green ink is an important area of ​​concern. In many countries in the Asia Pacific region, environmental regulations will become increasingly stringent, and some printers will find it difficult to adapt to this change in the current difficult economic situation, while ink manufacturers work hard to meet the requirements of these new standards.

The Asia-Pacific ink industry has seen a shift from traditional solvent-based inks to environmentally friendly inks such as water-based flexo inks, soybean oil inks, and UV inks. The development and production capacity of environmental inks has become one of the key factors for ink manufacturers to win in the Asia Pacific region in the future.

The current demand for toluene-based packaging gravure inks is still growing. Toluene-free nitrocellulose-based inks also have a certain market share in some large multinational packaging companies but are not very large. In Southeast Asia, UV-curable inks are increasingly popular, but so far a large number of these inks are still dependent on imports. In the end, these strict environmental protection regulations will be implemented. When environmental regulations come into effect, ink manufacturers must consider environmental issues, whether produced in-house or indirectly in the country. At present, there are no strict environmental protection laws in China for inks, but just as in the Chinese paint industry, environmental protection regulations for inks will be introduced sooner or later. Non-volatile organic (VOC) inks and water-based inks have been tested in the minds of each ink manufacturer or in the laboratory, so that they can be put on the market quickly when environmental regulations are introduced.

In Malaysia, aqueous flexo inks are rapidly growing and replacing gravure inks, although gravure inks still dominate. In the Philippines, concerns about the environment and health issues have also prompted petroleum-based inks to be replaced by water-based inks. In China, the issue of environmental protection has also received widespread attention from printers.

New digital printing disperse dye ink developed successfully in Germany

DyStar, Germany, introduced Jettex D, a digital direct-printing disperse dye ink for polyesters, which sets new standards to ensure optimal color depth and vividness, good color space coverage and contour definition, High color fastness and good fixing rate.

Jettex D inks are water-soluble disperse dye inks that are identical to disperse dyes used in conventional polyester textile printing to ensure maximum process reliability, size-like conversion, and color consistency. The ink is particularly suitable for banners and advertising materials, as well as digital inkjet printing for women's clothing.