Green Ink is the Only Way for Food Packaging and Printing Enterprises
Green food consumption has become a trend, but it is very inconsistent with it that many green foods do not use green packaging and green printing, but use some toxic and harmful substances as packaging and printing materials. Food packaging is known as "special food additives". As the "personal clothing" of food, its safety will directly affect the quality of food. Unqualified food packaging will have adverse effects on human health in the use process, especially on the healthy development of children and adolescents.
Zhang Liming, deputy director of the National Quality Supervision and Inspection Center for Printing and Decoration Products, said that solvent-based inks are still the main method of food packaging in China. These inks contain a large number of harmful solvents, such as benzene, toluene, xylene and so on. If benzene exceeds the standard, it will cause cancer, especially blood system diseases. In addition, the contents of heavy metals such as mercury, lead and arsenic in ink also have great harm to human body.
The internationally recognized printing ink for food must abide by the principle of non-transfer; the conventional printing ink should not be used when printing the inner surface of food packaging; the printer must ensure that all solvents in the printing ink volatilize, and the ink should be cured thoroughly, and meet the corresponding standards of the application industry. Thus, the role of ink in food packaging and printing can not be small.
Food packaging calls for environmentally friendly ink products
The safety of printing products will form a new green barrier to trade in China. From the production process of printed matter, ink has undoubtedly become the "protagonist" in this complete industrial chain. At present, most countries in the world advocate the use of environmental protection ink, alcohol-soluble ink and water-based ink, especially water-based ink as green environmental protection ink is more and more widely used.
Water-based ink: Water-based ink is currently used in most flexographic packaging printing inks at home and abroad. It is mainly made of water-soluble resin, organic pigments, solvents and related additives by composite grinding. Water-soluble resin is the binder of water-based ink. Water-soluble acrylic modified resin is often used as binder in our country. Its heat resistance, weather resistance, chemical resistance, pollution resistance and glossiness have obvious advantages. Both direct dispersive dissolution and synthesis of polymer emulsion show excellent performance. Water-based ink does not contain volatile organic solvents, which can not only reduce the printing residue. It is a new type of "green" printing ink, which is toxic and can prevent ignition due to contact between static electricity and flammable solvents. Water-based ink is also the best substitute for benzene-soluble ink.
Ultraviolet curing ink: Ultraviolet curing ink refers to a certain wavelength of ultraviolet light irradiation, the linker in the ink occurs cross-linking reaction, from liquid to solid to complete the curing of the ink, it is before the linker dissolves, macromolecular prepolymer is firmly formed ink film. Ultraviolet curing ink is mainly used for flexible printing of soft substrates. It consists of prepolymer, reactive diluent, pigment, additive, photoinitiator/synthesizer.
Electron Beam Curing Ink: Electron Beam Curing Ink refers to the ink that can rapidly change from liquid to solid under the irradiation of high-energy electron beam, also known as EB ink. Most of the food and beverage packaging industry uses electron beam curing printing, which is offset printing. EB ink is suitable for the development direction of high-speed and multi-color primary printing in printing industry. The main difference between EB ink and LIV curing ink is whether there is a photoinitiator in the binder. When a certain amount of photoinitiator is added to EB ink, UV curing can also be carried out. EB can solidify thicker ink layer. Because there is no photoinitiator in the ink, the cost is lower than that of LIV ink, but the investment of EB curing equipment is higher than that of LIV curing.
Digital printing ink: Digital printing technology has penetrated into the food packaging and printing industry with the increasing demand for personalized packaging. Digital printing technology can achieve high image resolution and reproduce image details ideally. Most of the printing materials are foil, metal aluminium, PET (polyester), paper and so on, and suitable for printing web paper. Solvent resistance is also very important for electrostatic digital printing. Prints with poor solvent resistance will not be able to complete the subsequent processes, such as polishing, film coating, etc.
