Packaging ink development trend

Printing is the third pillar industry in developed countries except for automobiles and petroleum, and ink is an indispensable raw material in the printing industry. At present, China's ink industry already has a considerable scale, with more than 300 production companies, of which more than 30 have considerable scale and production and research and development capabilities. The total production capacity of ink is approximately 220,000 tons per year, ranking fourth in the world. The overall output of 5-6%, in general, although China's ink can basically meet the needs of the domestic printing and packaging industry, but compared with foreign advanced level, there is still a considerable gap. After joining the WTO, China's ink industry needs rapid development and narrowing the gap with the world's advanced level.

The packaging industry is an important growth area for ink worldwide, because the demand for food, drink, and medication is stable regardless of economic conditions. The trend in the packaging market has confirmed that there will certainly be development after the economic downturn. For the ink-manufacturing industry, the packaging process is also an edge science that can be continuously improved, and there will be continuous improvement in new technologies and processes.

The important development trend of current packaging printing materials is to improve their environmental performance, choose energy-saving, low-cost, non-toxic, non-polluting, and easily degradable pollution-free packaging materials, and ink is a raw material that causes more serious pollution, therefore, how to reduce the ink The environmental pollution and energy consumption have become the most important development direction of the ink industry.

To fundamentally improve the impact of ink on the environment, we must start from changing the composition of the ink, that is, as far as possible the use of environmentally friendly materials to formulate a new environment-friendly ink, in order to reduce VOC emissions and improve energy efficiency. At present, the environment-friendly ink mainly includes water-based inks, UV-curable inks, and water-based UV inks.

The biggest difference between water-based inks and solvent-based inks is that the solvents used in water-based inks are water and ethanol. The VOC content is extremely low, and the environmental pollution is small. In the flexible packaging industry, solvent-based inks are mainly based on volatile drying. The lower the boiling point of the solvent, the more volatile it is and the more toxic gas is released to pollute the environment. After printing, there are residual toxic substances on the surface. The solvent used for the ink is water and ethanol excluded from the VOC list, which can greatly reduce VOC emissions. At present, more than 40% of American plastic film printing uses water-based ink, and other developed countries use water-based ink more and more in flexible packaging. In the United States, water-based inks complying with VOC regulations must meet the following two standards: 1. In the ink composition of the use state, the proportion of volatile components is less than 25%, and the water content is more than 75; 2. The ink with less moisture is in use. , Non-volatile components are above 60%. In recent years, China has also made some provisions for the packaging of food. The status of “green” printing is continuously improving in China. At present, China's flexible packaging of water-based inks ranks first among other printing inks at a consumption of 35%.

UV inks are inks that use ultraviolet light of different wavelengths and energies to form and dry inks under ultraviolet light. Using different UV spectra, different energy can be generated to polymerize the monomers in different ink binders into polymers, so the UV ink film has good mechanical and chemical properties. The main advantages of UV inks are as follows: 1. No solvent is used to fundamentally avoid the pollution of the VOCs to the environment; 2. The drying speed is quick and the energy consumption is low; 3. The gloss is good and the color is bright; 4. The water resistance, solvent resistance, and wear resistance Good performance. The main components of UV inks include pigments, photopolymerizable prepolymers, photopolymerization initiators and additives. Among them, the prepolymer is the main functional component, and there are three major types of commonly used prepolymers: epoxy acrylate, amine ester acrylate and polyester acrylate. At present, UV ink has become a relatively mature ink technology. Its pollutant emission is almost zero, and it has a reputation as an energy-saving and environment-friendly "green" product. According to statistics, the annual output of UV inks is approximately 16,000 tons in Japan, approximately 18,000 tons in Europe, and approximately 19,000 tons in North America, of which flexo inks and offset inks are the most rapidly growing.

Water-based UV inks are a new research direction in the field of UV inks. Since the viscosity of the prepolymer in the general UV ink is generally very large, it is necessary to add a reactive diluent to dilute, and the currently used diluent acrylate compounds have different degrees of skin irritation and toxicity, so in the development of low viscosity pre While developing polymers and low-toxicity reactive diluents, another development direction is to study water-based UV inks, that is, UV inks using water and ethanol as diluents, which can achieve even lower toxicity when VOC emissions are still low. . According to reports, water-based UV solder mask inks have been developed, and the United States has also successfully developed water-based UV inks for printing.

In short, only the continuous use of advanced technology and the development of "green packaging printing inks" and other functional ink products that meet environmental protection requirements can bring new development opportunities to China's packaging industry.