Overview of the development of the hottest water-b

Overview of the development of water-based inks (Part 1)

this paper introduces the application and technical development of water-based inks in China. The application of ink flexographic printing in food packaging was introduced in detail. Finally, the development trend of water-based ink is pointed out

I. application of water-based ink in China

China's water-based ink came out in 1975. It was first developed and put into production by Tianjin ink factory. At that time, it was mainly used for gravure printing. In the 1990s, China's economy has developed rapidly, and people's awareness of packaging aesthetics and environmental protection has been continuously improved. From 1995 to the end of 1998, China has introduced more than 130 combined flexographic printing production lines in just a few years, which are distributed in more than 20 provinces and cities across the country, 90% of which are narrow width flexographic printing machines. Now the number is increasing by about 30 every year, and there are many imported high-end three-color and four-color water-based ink printing slotting machines for corrugated paper color printing

the introduction and development of flexographic printing in China began in the 1970s. Now we have been able to manufacture flexographic printing machines and their substrates, as well as various flexible printing inks. In particular, the standardized production of water-based inks and water-based polishes can be added to other types of inks. 2. Measuring the model one color water-based polishes, which blocks the volatilization of other toxic solvents; It can also be in direct contact with food, ensuring food safety and hygiene

in China, flexographic packaging printing has made great progress in the past 10 years, but the development momentum is not fast and the progress is not significant. At present, flexographic printing only accounts for about 3% of the printing field. However, with the gradual popularity of green packaging and environmental protection packaging, many cigarette factories, distilleries, pharmaceutical factories, cosmetics, children's toys and other enterprises are allowed to introduce the project investors to use flexographic printing product packaging. The proportion of flexographic printing in the printing field will gradually increase, especially in the field of packaging and printing. It is estimated that flexographic printing will reach about 15% in the printing field by 2010, and the annual demand for water-based ink is more than 100000 tons. Therefore, it is urgent to vigorously develop, develop and produce high-grade water-based inks, and the market potential is great

II. Overview of the development of water-based ink technology

at present, the types of inks used for gravure printing are roughly divided into oil-based inks and water-based inks. The difference lies in the carrier used. The carrier of oil-based ink is organic solvent, while the carrier of water-based ink is water and alcohol. The so-called organic solvent is a general term for solvents that use toluene, ethyl acetate and other chemical substances. Generally speaking,

water based ink is also called liquid ink. In appearance, because water-based ink uses more water, it seems that there is no other difference except for the overall clarity. In addition, in terms of flexible packaging, the printing surface is made of plastic film into a sandwich like three-layer structure, and the printing part will not directly touch the contents, so it seems no problem to print with oily ink, but the organic solvent is composed of chemical substances with very fast volatilization speed, and a small amount of solvent in the ink will penetrate through the film and penetrate into the outside or inside of the bag. When we open the bag of snacks, we often smell the peculiar odor, that is, the odor of organic solvents (chemicals) penetrating out. Almost all the chemicals used in oily inks have a special irritating odor. Nowadays, the solvent filled in the bag is called residual solvent. And the appearance of this residual solvent is a headache for oily inks. Water based ink solvent basically uses only water and alcohol, which can effectively solve the above problems, and now has attracted attention

when using oily ink, the depth of the concave hole of the drum is 30 μ M up and down, but the shallow version roller used for water-based ink has a concave hole depth of 12 ~ 15 μ M is enough. Therefore, as long as water-based ink is successful, it is related to reducing the coating amount of ink. After testing, compared with oil-based ink, the coating amount is reduced by about 10%. In addition, the printing plate used for water-based ink uses dark ink because of its shallow version, and the reproducibility of ink color is better than that of oil-based ink. Of course, water-based ink also has disadvantages. Compared with oil-based ink, its carrier needs to extend the drying time because of its slow drying speed. Prolonging the drying time is equivalent to slowing down the printing speed. In addition, when using water-based ink, it is necessary to improve the original equipment or introduce new corresponding models

water based inks are no inferior to oil-based inks in printing and finished products. At present, there are still funds that need to invest in transformation technology. Therefore, it is not necessary to change the environment to use water-based ink at once, but from the perspective of environmental protection, the ratio of water-based ink should be gradually increased

III. Development Trends of water-based ink technology

at present, whether imported or domestic water-based ink, there are disadvantages such as non alkali resistance, non ethanol resistance, non water resistance, slow drying, poor gloss, and easy to cause paper shrinkage. To overcome the above shortcomings, some use UV ink, which not only increases the printing process, but also increases the printing cost. Some use high-end imported high-end water-based ink, It also increases printing costs. Therefore, we should further strengthen the development of high-performance water-based inks

1. High temperature resistance

a high temperature water-based ink for corrugated box preprint has been successfully developed in Shanghai, which timely fills the gap of this technology in the domestic ink industry and lays a foundation for the improvement of print quality. This kind of water-based ink is the first in China and has the best effect compared with the current high-temperature water-based ink. Last year, Sichuan Deyang today Color Printing Co., Ltd. introduced a 1.2 m web printing machine from Italy, which is a satellite type intaglio ink pre printing equipment. The water-based ink of this machine can't pass the test in the trial production stage, including the imported water-based ink, because the cardboard paste on the corrugated board production line needs to be treated at 180 ~ 200 ℃. Fuqide company and Deyang cooperated to accept this scientific research project. After six months of repeated trial production, it was finally successful not long ago

the ink has the following characteristics: (1) high temperature resistance. At a high temperature of 200 ℃, the ink will not change color, and will not wrinkle or bubble, maintaining the inherent printing effect and effectively ensuring the quality of prints. (2) Abrasion resistant. In the process of container transportation, it is ensured that prints can still maintain the invariance of printing color after being collided and rubbed with each other, which increases with the experimental force. (3) Fast drying speed. Generally, in high-speed printing operations, due to the speed, the ink cannot be completely dried, which will cause quality problems such as ink dragging and ink pasting. The drying speed of the new ink has been further improved, slowing down the occurrence of this adverse phenomenon. (4) With low viscosity, high color concentration, bright and beautiful color, this special water-based ink is suitable for printing on the surface of coated white card and polished white card box. When it is used on a multi-color water-based printing machine, it can also be used after removing the high-temperature formula and reducing the ink production cost

2. Environmental protection

the series of water-based inks developed by Wuhan Institute of modern industrial technology are non-toxic, non irritating odor, non corrosive, non combustible, non explosive and safe to use. As a new green printing material, it has obtained a national patent and passed the inspection and identification of the national ink quality inspection center. The new ink series production technology can be widely used in the printing of gold, silver cardboard, coated paper, whiteboard, corrugated paper, self-adhesive paper, cartons, paper packaging bags, books and magazines, etc

ammonia is usually used for water-soluble acrylic resin and other water-soluble resins. Two methods have been developed to reduce ammonia odor. First, we use odorless amines with slightly less volatility to replace a small part of ammonia, and the addition amount is the most appropriate when the pH is about 8.1. At this time, the resin still has good solubility, and there is almost no ammonia taste. All ammonia combines with the resin to form ammonium salt. If you try to avoid using other amines, you can reduce the residual amount of ammonia, but this will lead to higher viscosity of resin solution or dispersion. Such low odor products include hydro rez3110 and 4120. It is also possible not to use ammonia or amines at all. These ammonia/amine free inks use a unique system consisting of sulfonated polyester resin and water-soluble acrylic resin