Increased demand for environmental protection and specialty inks (1)

Experts predict that the recent demand for ink in the Chinese market will increase at a rate of 9% per annum. The annual growth rate of inks in the publishing industry will reach 8% to 10%, while the annual growth rate of inks in the packaging industry will reach 12%. Among them, environmental protection and specialty inks will show particularly rapid growth.

It is estimated that the total amount of printing ink consumption in China will reach 300,000 tons in 2005, and consumption will increase even more in the next few years. Upright bag packaging, fresh produce packaging, pharmaceutical packaging, and corrugated packaging used in the food industry all provide growth opportunities for inks. On the one hand, as people's demands for quality of life and survival and development of the environment continue to increase, the product packaging market calls for "green ink"; on the other hand, people hope that the packaging effect is more beautiful, more diversified, can meet a variety of special-purpose ink Will be favored.

Green ink

In order to fundamentally improve the impact on the environment, we should start from the aspect of changing the composition of the ink, using environmentally friendly materials as far as possible to formulate a new type of environmentally friendly ink. At present, environmental protection inks mainly include water-based inks, UV inks, and alcohol-soluble inks.

Water-based ink

Water-based inks are the only inks approved by the U.S. Food and Drug Association in all printing inks. The biggest difference between it and solvent-based ink is that the solvent used is water instead of organic solvent, which significantly reduces VOC emissions, prevents air pollution, does not affect human health, and is particularly suitable for strict sanitary conditions such as food, beverage, and pharmaceuticals. Packaging printing products. In addition, it can not only reduce the risk of fire and hidden dangers caused by static electricity and flammable solvents, but also reduce the residual toxicity of printed surfaces. However, water-based inks also have deficiencies. They are not resistant to blemishes, they are not resistant to ethanol and water, they are slow to dry, they have poor gloss, and they can easily cause paper shrinkage, which greatly restricts the use of inks where glossiness is high and refrigeration is needed.

In China, the application of water-based inks is not very popular, and there is still a certain gap compared with developed countries. In Europe and the United States, water-based inks used in the packaging industry accounted for 80% of the entire package printing, while China accounted for only about 7%. In China, water-based inks are mainly used for flexo printing, and the printing materials are mainly absorbent media such as paper. In recent years, the rapid development of the packaging industry, especially the extensive use of photosensitive resin plates and laser ceramic anilox rollers, has made the development of flexographic printing more accelerating and at the same time led to the rapid development of flexographic printing inks. With the gradual implementation of China's ISO14000 environmental management system, the development prospect of water-based ink is very considerable. It is estimated that by 2010, flexographic printing will reach about 15% in the printing field, and annual demand will be more than 100,000 tons of water-based ink, which will account for 25%-30% of the total ink consumption. Therefore, it is imperative to vigorously develop and produce high-grade water-based inks.

UV ink

UV ink is an environmentally friendly ink that has developed rapidly in recent years. It quickly occupies the market with instant curing (drying), free of volatile solvents, and simple and convenient application. UV ink refers to an ink that uses ultraviolet light of different wavelengths and energy to form and dry an ink under ultraviolet irradiation. The main advantages include: no solvent; fast drying speed; low energy consumption; colorful; water and solvent resistance; good wear resistance.

Water-based UV inks are a new research direction in the UV ink field. The viscosity of prepolymers in general UV inks is generally very large and needs to be diluted with a reactive diluent. However, currently used thinner acrylate compounds have different degrees of skin irritation and toxicity. Therefore, while developing low-viscosity prepolymers and low-toxicity reactive diluents, another development direction is to study water-based UV inks, ie, water. Ethanol and other diluents.

UV printing is currently mainly used for the packaging and printing of non-absorbent materials such as gold/silver cardboard, aluminized paper, and plastics. UV inks give prints high quality and high gloss, but also bring a lot of trouble to the operation, for example, , UV ink ink balance tolerance is very narrow, easy to cause ink emulsification during printing, affect the stability of the printing quality; Another example, due to the UV ink superposition printing performance is poor, the need to add a middle seat in the printing color group for curing To improve the effect of overlay printing, and this undoubtedly increases hardware investment.

Alcohol soluble ink

Since aqueous 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 inks have now been applied in the domestic gravure printing industry. Alcohol-soluble synthetic resin, solvent and organic pigment are fully ground and dispersed to form a gelled liquid with good fluidity. It is a volatile dry ink with the characteristics of fast drying, bright luster and bright colors. This ink does not contain aromatic hydrocarbons and does not contain ketone solvents. It contains only esters and alcohol solvents, which can effectively solve the health problems caused by toluene inks and solvent residues affect the quality of packaged foods. It is suitable for printing and packaging. Food cellophane and candy wrappers. The disadvantage is that it is difficult to adjust the volatilization speed and printability is poor.

In Europe and the United States, the use of alcohol-soluble gravure ink has become a trend; in Asia, such as Singapore, South Korea and other countries, alcohol-soluble gravure ink is gradually replacing the toluene ink. Although the use of alcohol-soluble inks is currently relatively small in China, its growth rate is accelerating. It can be predicted that in the near future, alcohol-soluble inks will occupy a major share of China's high-grade food and pharmaceutical flexible packaging ink market.