Development of plastic flexible packaging printing and ink at home and abroad (in Chinese)

Differences in Development of Plastic Flexible Packaging Market at Home and Abroad

In the new century, with the continuous improvement of plastic packaging materials and processing technology, the development of plastic flexible packaging at home and abroad has produced many differences. First of all, foreign countries focus on improving the functionality of packaging products (the first is to preserve the intrinsic value of the packaged goods), the ease of use, the pursuit of the color of the brand representative of the specificity; printing machine to the low color element (with three or four color printing press Mainly, high speed, batch, automation development. However, in China, packaging design has been made colorful, imitative, over-packaging, and increasingly decorative. The price competition is fierce, and the original functionality of the packaging is neglected (the function of preserving the intrinsic value of the contents being packaged), and the performance is poor, and the printing press develops toward multi-color metamorphism (the gravure printing units introduced in the early 1980s had only five colors and six colors. Color, up to seven colors; now introduced and domestic gravure printing unit eight-color, nine-color popular, ten colors, twelve colors, fourteen colors, and even more colors).

The replacement of flexible packaging production equipment has changed from a cycle of the past decade to a cycle of 3-2 years. In recent years, the replacement period has become shorter, especially the upgrading of electronic control equipment, and it is changing with each passing day. The production equipment is more and more advanced, but the improvement of the technical quality of the operators is slow, and even there are retrogressive phenomena. Why is this?

Two are not... Three are not standardized

This is because the current domestic packaging market is not standardized and the national standards are lagging and loose, and the citizens' awareness of packaging is poor. The domestic plastic gravure printing machine is uneven and has a large disparity in performance. The variety of packaging, and the small number of batches, frequent replacement of raw materials. The processing companies compete with each other in price competition, the material selection is poor, and the production environment is not standardized.

Currently, there are few exchanges among domestic flexible packaging manufacturers. In the flexible packaging technology seminars, there are many abstract and profound theoretical knowledge, many product promotion, and less applied knowledge and practical technologies. There is a lack of technical data on the application, manufacture, and selection of materials, and there is no generalization of professional knowledge. There is no book on the integration of theory with the actual plastic intaglio printing technology, plastic flexible packaging compounding and material selection technology. The flow of employees in packaging manufacturing enterprises is too frequent, the basic knowledge of packaging applications is lacking, the theoretical knowledge of gravure printing technology is poor, and the operation technology of gravure printing technology is not comprehensive, and the training of workers is not in place.

There is no two: There is not a specialized university in China that produces plastic flexible packaging technology. There is no textbook that spreads knowledge about the application of plastic flexible packaging. Three non-standard: First, China's plastic flexible packaging equipment manufacturers production equipment (can only produce equipment with the economic and technical strength of the company's limited equipment) irregular uneven. Second, many domestic ink manufacturers, comply with the needs of more than 90% of the large market, the production of low-priced ink is not standardized. Third, it is the middle and small-sized plastic packaging companies that have low-grade production equipment, use low-priced inks, and have poor management and weak technical strength, resulting in non-standard products.

Therefore, the technology of plastic flexible packaging can only be taught without being able to pass on words. The printing technology relies on spontaneous exploration and accumulation by experience; the lack of senior energy, young experience has not yet been accumulated, the packaging companies generally lack skilled workers, and skilled craftsmen are serious shortages. .

The status of domestic plastic gravure printing ink companies and markets

Of course, printing is inseparable from the ink, and the characters and patterns on the packaging are the embodiment of the ink on the packaging. Over the years, China's ink production companies have continued to increase. The various inks used in gravure printing can be produced in China. Both the quality and quantity can meet the needs of gravure printing production. In addition, the quality of inks has generally improved, and the gap with foreign products is getting smaller and smaller. However, the low-priced inks produced by many domestic ink manufacturers are not 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 inks only require high solid content, low viscosity, brilliant color, and strong coloring power. Many domestic medium and low-speed printers are the main products, and domestically produced printers are uneven, with huge performance gaps, small product quantities, various types of products, poor production environments, unregulated operations, and fierce price competition. It is hoped that the ink will have strong adaptability, good fluidity, and a low price. Then the operator's mentality, using imported ink, printing problems, find the reasons for the operation, adjust the press. In turn, printing out problems with domestic inks is definitely a matter of finding inks and printing plates. Secondly, the ink circulation system of domestic gravure printing machines is poor (except for high-speed printing machines that deliver ink supply), and many northern and middle-sized packaging printing plants do not use an ink circulation system. Once again, I do not know the law of the ink on the gravure printing. Little is known about the performance of the ink. The dilution of the ink is not in place. It is observed that the wastage rate of the ink is on average 25% to 30%. There are many small-scale packaging printing plants and even a wasteful rate of 40. % to 50%). Therefore, it is more necessary to popularize the basic knowledge education of the production technology of plastic flexible packaging, as well as technical services after ink sales.

At present, gravure printing inks used in China contain a large amount of organic solvents (about 50%). Toluene, ethyl acetate, butanone and other solvents have low boiling points, high volatility, aromatic hydrocarbons, and are toxic and flammable. They are the main sources of environmental pollution. 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. Chlorofluorocarbon gases that are volatilized during the production of chlorinated polymer inks can destroy the atmospheric ozone layer. The use of aromatic solvents (toluene) in the production and printing of inks can harm workers' health and safety (fire risks). In addition, the problem of ink solvent residue in packaging products is a concern. Benzene can easily remain in the dry ink film layer (low-speed printing requires the use of xylene to adjust the drying speed of the ink, xylene is more likely to remain), and benzene residues can contaminate the food or articles in the package. Although the gravure alcohol ester ink is the leader of the alcohol-soluble ink, although there is no benzene-free ketone, it will still pollute the environment and there will be residual solvent.

The production of plastic gravure inks is subject to laws and regulations such as Fire Protection Law, Labor Safety Law, and Health Law. Therefore, it is an inevitable trend to actively develop and apply green gravure inks and water-based inks that meet the requirements of environmental protection. Although water-based gravure ink as a solvent-based ink replacement system has attracted the attention of various sectors, the ink in packaging film printing is still not yet in a practical stage. In general, the important reason why water-based gravure printing inks have not been popularized further is that printing performance and quality still cannot meet the standard for printing of solvent-based gravure inks. Mainly due to the greater surface tension of water, resulting in difficult to wet the ink; water does not volatilize, printing speed can not go up. If the printing speed and the printing quality of the gravure solvent ink are to be obtained, not only the aqueous ink itself needs advanced technology improvements, but the gravure printing apparatus and the printing plate roller also need to be improved. For example, a corrugated or electroetched roll with a depth of approximately 38 - 42 micrometers in the printing roll is changed to a laser making roll with a web depth of approximately 24 - 28 micrometers. The print roll also needs to be made of a corrosion-resistant material. There is also a need for a more powerful, effective ink drying system, and ink squeegee and other equipment components on the press, all of which require considerable investment and long time.