Plastic flexible packaging printing ink market outlook

Yang Weimin (Chief Engineer of Yihua Plastic Flexible Packaging New Technology Co., Ltd.):

In recent years, the quality of domestic ink has generally been improved, and the gap with foreign products is getting smaller and smaller, but the low-priced ink produced by many domestic ink manufacturers is not yet standardized.

The printing speed of foreign printing presses is fast, the production environment is more standardized, and the varieties are bulky and color-specific. Therefore, the ink requires high solid content, low viscosity, brilliant color, and strong coloring power. Most of the domestic medium- and low-speed printing presses are the main products, and the domestically produced printing presses are uneven, and the performance is very different. The products have small quantities, many varieties, poor production environments, unregulated operations, and fierce price competition. This requires strong ink adaptability, good fluidity, and low price.

At present, gravure printing inks used in China contain a large amount of organic solvents (about 50%). Intaglio printing inks 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 is adjusted with toluene during the printing process. However, solvents such as toluene, ethyl acetate and butanone have low boiling points, high volatility, and aromatic hydrocarbons, which are both toxic and flammable and are the main sources of environmental pollution. The chlorofluorocarbon gases that are emitted from the chlorinated polymer inks during production can destroy the atmospheric ozone layer. The use of aromatic solvents (toluene) can also harm workers' health and safety (fire hazards) during ink production and printing.

In addition, benzene can easily remain in the dried ink film layer of plastic flexible packaging printing products (low-speed printing requires the use of xylene to adjust the drying speed of the ink, xylene is more likely to remain), benzene residues can contaminate the food in the package or Supplies. Therefore, the ink industry has been working hard to develop alcohol-soluble inks with less environmental pollution. Alcohol-soluble inks can solve the problem of Benzene and benzene residues caused by the health of toluene-based inks.

Toluene inks have been eliminated in countries such as Japan, South Korea and Southeast Asia. Europe also strongly advocates flexo (Toppan printing) printing.

However, gravure printing can only use alcohol-soluble ink, so alcohol-soluble ink instead of benzene-soluble ink is the inevitable trend of the development of China's plastic flexible packaging printing ink.

In spite of this, benzene-free, ketone-free inks still have environmental pollution and solvent residues. For this reason, the water-based gravure ink as a solvent-based ink replacement system has attracted the attention of various departments, but the ink in the plastic film printing is water-based and has not yet reached a real practical stage. From a general point of view, the long-term lack of further popularization of water-based gravure inks is due to the fact that the print performance and quality still cannot meet the standard for solvent-based ink printing.
Due to the large surface tension of water, the ink is difficult to wet, the water does not volatilize, and the printing speed does not go up. If we want to obtain the printing speed and printing quality of the solvent ink, not only the aqueous ink itself needs to be improved, but also the gravure printing apparatus and the printing plate roller need to be improved. For example: The corrosion or electric engraving roller is changed to a laser plate making roller, and the printing plate roller also needs to be made of a corrosion-resistant material. There is also a need to retrofit more powerful ink drying systems and ink squeegee equipment components on the press, all of which require considerable investment and long time. Therefore, the water-based gravure ink cannot be used as a substitute for solvent inks except for printing on paper.

How can produce a single solvent (easy to recycle), table printing, printing, compounding, cooking and cooking; all kinds of plastic film are applicable, any climate is adaptable (can reduce the production cost of the enterprise), high speed, medium speed, low speed All suitable and inexpensive gravure inks are expected by the domestic gravure printing industry.

At the All India Exhibition in Shanghai in 2006, Zhejiang Fangbang Machinery Co., Ltd. and Xi'an Aerospace Huayang Co., Ltd. exhibited a high-speed letterpress (flexo) printing machine at the same time. Baoding Gelsida, Dalian, and other plastic printing companies also introduced foreign countries. The advanced high-speed letterpress (flexo) printing machine caters to the needs of packaging in the dairy industry in China and solves the environmental pollution and residual problems of benzene solvents. It has become a new competitive highlight for plastic flexible packaging printing. Therefore, it has developed and produced low-cost, high-performance products. Toppan (flexo) inks have also become the target of ink manufacturers.