Green environmental protection of the hottest flex

The so-called green packaging should have five connotations: first, implement the reduction of packaging; Second, the packaging should be easy to reuse or recycle; Third, packaging waste can be degraded; Fourth, packaging materials should be non-toxic and harmless to human beings. The package should not contain toxic elements, bacteria and heavy metals; Or these contents should be controlled below the relevant standards; Fifthly, the whole life process of packaging products from raw material collection, material processing, product manufacturing, product treatment, waste recycling to final treatment should not cause public hazards to human body and environment. Food packaging is the last process of modern food industry. It plays an important role in packaging, protection, beautification, publicity and convenience of food storage, transportation and sales. To a certain extent, food packaging has become an important part of food. At present, the situation faced by China's food packaging industry is not optimistic. Many food packaging materials in the market are difficult to meet the national requirements for food safety, health and environmental protection, such as the toxicity and residue of solvents, the content of heavy metals, etc., which not only endanger health, but also affect the healthy development of China's food packaging industry, and even the whole food industry. After joining the WTO, "technical barriers to trade" has become the biggest challenge faced by many export enterprises in China. At present, benzene solvent-based inks account for a large proportion of plastic gravure printing inks in China, while developed countries such as Europe and the United States clearly prohibit the use of benzene solvents in food packaging and printing. Therefore, the application of alcohol soluble, water-based and other environmental friendly benzene free inks in plastic gravure printing will be increasingly concerned by the industry, and will dominate the future ink printing market. At the beginning of 2005, three years after China's accession to the WTO, "develop green and environmentally friendly flexible packaging" and "connect with the international community", these words seem to be mentioned by more and more domestic flexible packaging enterprises, large and small. The voice of environmental protection is rising in the academic circles and the field of flexible packaging industry. At the same time, the domestic flexible packaging industry is practicing this mainstream, and a series of environmental protection policies, regulations, measures and products are gradually introduced, such as legislation to prevent excessive packaging, safety and environmental protection product certification, flexible version, solvent-free composite, degradable film, environmental friendly aluminum foil, etc. these policies, products and technologies are welcomed by consumers and the market

I. Development Trend of inks for flexible packaging

in China's plastic flexible packaging market, small and medium-sized enterprises account for the vast majority, and the products produced are not highly technical or similar, so the competition is very fierce. In the end, they often only focus on the reduction of costs, ignoring the technical and health requirements of products. Although the use of domestic plastic inks has increased significantly, the safety and health performance has not been improved correspondingly, and there is a significant lag phenomenon. Aromatic solvents such as toluene are still widely used, and chloropropyl printing inks account for more than 60% of the market

since China joined the WTO, the economy and trade between China and other countries have become closer. The requirement of "internationalization" has greatly promoted the development of China's plastic ink industry in the direction of environmental protection. The domestic plastic packaging ink must be linked with safety and hygiene in the future product research and development. As for its solvent system, it should develop towards benzene free and alcohol soluble. In terms of its binder technology, it should develop in the direction of polyester urethane system. Polyester polyurethane ink is favored by users because of its low toxicity, good printability for pet and NY materials, high temperature cooking resistance, freezing resistance, wear resistance and other excellent properties, and will gradually replace chlorinated polypropylene ink. Plastic packaging inks are clear and eye-catching in terms of their pigment system. It is said that they will develop in the direction of heavy metal free pigments. Domestic pigment manufacturers will face the risk of being eliminated if they cannot integrate with international manufacturers in this regard

in supermarkets in Europe and America, we found an interesting phenomenon: its product packaging is very simple, and its color and texture are different from those in China. If the flexible packaging is taken out separately and compared with similar products in China, it is believed that China's QC (quality control) department will treat the vast majority of western countries as inferior products. Why do developing countries catch up with developed countries in the field of packaging? We take American flexo printing as the starting point for analysis: and the company's research results show that flexo printing is slightly inferior to gravure printing in point performance, and the printing quality is low, but it takes the lead in environmental protection. First, the U.S. government has formulated tough environmental protection regulations; Secondly, due to the scale economy of flexo printing, 2 - the indentation depth under the total experimental force f0+f1; The cost of 882.6 is reduced, and manufacturers are willing to accept 882.6; Coupled with good social education, consumers tend to use environmentally friendly products. Therefore, the adoption rate of flexographic printing in flexible packaging in the United States is as high as 90%, and the country, businesses and consumers have become big winners in this environmental protection game. However, in China, flexographic printing and other environmental protection technologies are not highly accepted in the market. Because flexographic printing adopts the principle of embossing, compared with gravure printing with thick oil and heavy color, there are less coloring inks. It is relatively thin, and the coloring degree is not very high. In terms of brightness, it is not as bright as gravure printing. Domestic flexible packaging consumption has been in the mindset of gravure printing with strong coloring and high brightness for a long time, so it is not very able to accept this new environmental protection concept of printing technology for the time being. Moreover, the development of flexographic printing technology is also limited by the market itself. The environmental friendly ink required depends on imports for a long time, resulting in high costs, which is also a reason why flexographic printing cannot be widely promoted

in China, food plastic flexible packaging is heavy, gravure printing has an absolute advantage, has been in a steady state of development, and has a good development prospect. In large supermarkets, gravure printing products dominate the packaging of food and daily necessities. In view of the above analysis and the development status of gravure printing in China, we have reason to believe that gravure printing will continue to maintain its absolute leading position in plastic flexible packaging printing

II. Green environmental friendly ink - water based ink

water based ink refers to the volatile ink with water and some alcohols as solvents. The ink dries with the volatilization of water. The printing process has no pollution to the environment, the ink is non-toxic to human body, is not easy to burn, and has good safety. Solvent based inks also use volatile drying, but there is a large amount of volatile organic compounds released. Judging from the current situation in China, water ink mainly uses corrugated paper, paper gravure printing and some flexographic printing, which are rarely used in gravure printing of plastic film. Using water-based ink in plastic film printing is the internal requirement of gravure printing. On the one hand, in the printing of plastic flexible packaging, the advantages of gravure printing are very significant: the printing patterns are bright and expressive; It has a good printing rate, which can reach more than 1 million times; Realize seamless image printing. On the other hand, the adverse effects of gravure printing are also obvious. Due to the non absorbability of plastic film, a large number of organic solvents are used in the ink itself and in the actual printing process, which destroys the environment and harms human health. At present, BOPP film printing is the most used in gravure printing, and most of the inks used are chlorinated polypropylene internal printing inks. A large amount of toluene is used as solvent, and chlorine monomers are used in the resin production process, which brings hidden dangers of health and safety to people. Gravure printing industry to develop strengths and circumvent weaknesses, to achieve sustainable development, we must eliminate the negative environmental impact and safety and health hazards caused by gravure processing