Rapid development of water-based ink market

In the past, solvent-based inks were mainly based on volatile drying. The lower the boiling point of solvents, the more volatile they were and the toxic gases emitted polluted the environment. After printing, toxic substances remained on the surface.

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 content of VOC (organic volatiles) is extremely low, and the environmental pollution is small.

Water-based ink characteristics

Water-based inks are abbreviated as water inks and are produced by compounding and grinding of water-soluble resins, organic pigments, surfactants and related additives.

Water-based inks use solvents such as water and ethanol excluded from the VOC list, which can greatly reduce VOC emissions, reduce air pollution, and completely eliminate the harmful effects of certain toxic and harmful substances in solvent-based inks on human bodies and on packaged goods. Pollution has improved the overall environmental quality. Not only can it reduce the risk of fire and toxicity due to static electricity and flammable solvents, but it also facilitates cleaning of printing equipment, so water-based inks are known as a new type of “green” printing material.

　 Ink advantages

Through nearly 10 years to 15 years of technical improvement, the ink-and-wash system has successfully solved most of the original difficulties, such as difficult to use, ink storage, substrate limitations, corona treatment and surface tension, and a new generation of ink. The initial disadvantage has changed to an advantage, gradually growing and maturing. Its advantages are mainly reflected in the environmental and safety advantages of ink and ink. In many paper products, ink printing can be designed as low VOC or zero VOC.

The ink has the advantages of stability and low flammability. The ink has better viscosity stability due to the low volatility of water. A new generation of water-based products is easier to clean than solvent systems. The use of soapy water or weakly alkaline lotion to scrub can complete the entire cleaning of the printing press components, thereby increasing production efficiency.

Technical barriers

The ink-and-wash manufacturers have overcome most of the difficulties that existed previously in the ink-and-wash system and are actively working to resolve the existing difficulties. The difficulty in the application of ink-jet technology is:

Drying time is still the most important issue in ink applications. Unless the press is equipped with enough drying equipment, the printing speed will be affected. This is also the most important factor affecting the speed of the ink-washing process to replace solvent inks.

Since the ink is soluble in an alkaline solution, the use of the ink in a highly magnetic environment is limited.

The application of ink on frozen food packaging still does not have the solvent ink resistance, although the distance is rapidly shortened.

Due to the high surface free energy of the water component in the ink, the ink is difficult to wet and print well on many substrates.

Water-based ink environmental protection trend

Rapid market development

The main application fields of environment-friendly water-based inks are flexo printing and gravure printing. In the United States, 95% of flexographic prints and 80% of gravure prints use ink. Flexographic printing is still in its infancy in China and currently accounts for only about 3% of the printing industry. In the flexo package printing, the vast majority of domestic and foreign water-based ink printing.

Recently, ink manufacturers have improved the performance of the resin to make it more soluble, which means that the printing system can be run longer before cleaning, ie, the production efficiency is increased; the ink application requires continuous improvement in the application performance of the polyethylene substrate. . The ink-manufacturing industry is expected to increase the surface resistance of ink-and-ink printing, especially in terms of oil resistance, grease resistance, and better heat and freezing resistance.

International trends

Water-based inks have undergone improvements that have had a major impact on many areas of the printing industry, especially flexographic printing. It is foreseeable that ink painting will continue to grow. The future development of ink painting depends on the guidance of the EPA (the U.S. Environmental Protectibn Agency); depends on the printer's existing incineration, absorption, and disposal control equipment depreciation and whether it will turn to water-based printing; depends on ink manufacturers to further improve ink performance With a view to gaining more market share.

In the United States and some European countries, the use of solvent-based inks containing benzene has been banned and green inks have been replaced. At present, 40% of U.S. plastic printing uses water-based inks. Other developed countries, such as Japan, Germany, France, etc., are also increasingly using water-based inks in plastic film printing. The United Kingdom has already banned the use of solvent-based inks to print films for food packaging.

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%.