Improve the printing process and develop green printing
flexo printing has developed rapidly in Europe and the United States and other developed countries because of its good printing quality, a wide range of substrate materials, low investment, high efficiency, good environmental performance and other advantages. An important reason why flexographic printing takes the lead in the field of packaging is that it uses water-based ink and does not contain toxic organic substances, which is just in line with the green development trend of modern packaging and printing. The biggest feature of water-based ink is that it significantly reduces VOC emissions, thereby reducing air pollution and improving the working environment of the printing workshop. Because of its environmental protection characteristics, it is especially suitable for the packaging and printing of food, beverages, drugs and other items
UV ink without solvent can also be used for flexo printing, so there is no solvent emission and no environmental pollution. In short, due to the use of environmentally friendly green materials, flexographic printing is expanding its scope of application, and is even more dominant in the field of packaging and printing. Therefore, in order to achieve green printing, we must vigorously promote flexographic printing
try anhydrous offset printing and alcohol free printing
anhydrous offset printing uses ink repellent silicone resin coated plates. Removing the coating in the image and text part can absorb ink and realize image and text transfer, so there is no need for fountain solution to achieve ink and water balance. The fountain solution contains volatile isopropanol and other toxic organic substances, which will affect the function of kidney and lung, and even cause dermatitis or nervous system damage if inhaled by the human body for a long time. Generally, the inks used for waterless offset printing are soybean oil inks and aromatic free inks, which do not produce VOC, so they will not qualitatively affect human body and the environment. Therefore, China's investment in the water treatment industry will exceed 1trillion yuan. Removing the fountain solution and using non solvent inks can be said to be a major contribution of waterless offset printing to environmental protection
in addition to removing the fountain solution in the production process, we can also find its substitute to reduce the harm of IPA to workers' health and the environment. Alcohol free printing just meets the requirements. This substitute mainly comes from one or two chemicals of ethylene glycol and ether plus other additives, which has good environmental protection performance. Of course, the use of substitutes will also bring some new problems, such as the new fountain solution volatilizes too slowly, which is not conducive to the cooling of the machine, and substitutes are not as effective as alcohol in disinfecting the fountain system
develop the digital printing market
because digital printing is directly from computer to print, there is no need for film and printing plate, which saves many intermediate steps of traditional printing and avoids the use of toxic chemicals such as developer. Digital printing adopts new imaging technology, which can largely avoid a series of problems caused by the volatilization of organic solvents in the process of image and text transfer in traditional printing. The main imaging principles of digital printing are as follows:
electrostatic photography
its basic principle is to use the laser scanning method to form an electrostatic latent image on the photoconductor, then use the Coulomb force between the charged toner and the electrostatic latent image to realize the visualization of the latent image, and finally transfer the toner to the substrate. Because electrostatic photography uses toner, there is no volatile organic compounds in the whole printing process. It is a pollution-free imaging technology
inkjet printing
spray the ink from the fine nozzle to the substrate at a certain speed, and finally realize the reproduction of the ink image through the interaction between the ink and the substrate. According to the way of inkjet, it can be divided into continuous inkjet and on-demand inkjet
magnetic recording imaging, the core technology for the production of a number of high value-added fluorine-containing high molecular materials, relies on magnetic materials to form a latent image under the action of an external magnetic field, and then uses the interaction between magnetic toner and the magnetic force of the latent image to complete the visualization of the latent image, and finally transfers the magnetic toner to the substrate to complete the printing
electrocoagulation imaging
the ink condenses through the electrochemical reaction, so that the ink is fixed on the surface of the imaging drum to form an image. The ink that does not react in the non graphic part is still liquid and can be scraped off. Finally, the ink fixed on the surface of the drum can be transferred to the substrate through the action of pressure
eliminate the process of film coating and plastic coating
in order to beautify and protect the mountains, many printed materials now need to be film coated and plastic coated, but this process will cause serious environmental pollution. First of all, it will cause white pollution like the plastic products we usually use. The film covered on the surface of printed matter is as difficult to degrade as other plastic products, and benzene is involved in the processing, which is harmful to human health. In addition, the coated paper can not be recycled, which wastes resources. The source of cellulose in papermaking in China is the recycling of old paper, which is made into pulp after deinking and recycled. However, the coated paper cannot be recycled. On the contrary, if it is simply incinerated, it will cause secondary pollution. Problems such as blistering, folding and film falling off often occur in the film covering process. Therefore, the film covering and plastic coating process is a technology that destroys the environment. We should avoid using this post press processing process
adopt environmental friendly glazing paint
post press glazing, like film coating, can also protect the cover and improve the gloss of prints, but the process is simpler than film coating and the cost is lower. In the past, solvent based polish was used, and VOC volatilized during use, which was very unsafe and did great damage to the environment. The new water-based glazing oil and UV glazing oil do not contain solvents and can be widely used. Especially in the field of packaging and printing, because water-based varnish will not cause harm to human body, it has been widely used in the packaging of cigarette labels, wine labels, food packaging bags and other products. The inflation rate in Turkey is controlled at about 5%
in addition to the above main ways, as long as we are a conscientious person in production practice, we will find more ways to improve the printing process and realize green printing. In short, print is everywhere, and printing is closely related to people. Green printing is not only related to the long-term interests of the printing industry itself, but also related to the coordinated development of the whole society. How to realize green printing, every enterprise should formulate a reasonable plan according to its own actual situation. Only in this way can we realize the sustainable development of the printing industry and make the printing industry prosperous
source: Chinese ink