Application of UV Printing Ink on Film (1)

After more than ten years of exploration on non-absorbing light-cured offset printing inks, this paper believes that an effective way to solve the problems of adhesion, increase flow, prevent photon decomposition, reduce ink cost, and improve ink properties is to add LJJTM to its system. Additives. Here, I would like to discuss with the insiders and outsiders about the author's little bit of practice.
First, the prospect of UV ink Ink UV refers to the use of ultraviolet light curing lithographic, flexographic, gravure, silk screen printing ink and other abbreviation. In the past 30 years, people have been working hard, improving, and trying to use it as a new edge discipline in green packaging printing inks, due to their small pollution and quick drying. Less energy consumption has become a new international fashion. "It's also a fresh air and a clean and pleasant land" has long been a common voice of people in the packaging and printing industry. But really high-speed, full-automated, photo-realistic offset printing, especially UV inks on non-absorbing non-polar materials are rare. The reasons are: the cost is too high, the adhesion is poor, the low temperature does not flow (usually by heating), the film formation process, even after the film formation photon may be decomposed (free radicals) and so on and has been limited by the scope of application. Followed by the film crisp, in the PVC electrostatic film on the screen easily lost or friction off the toner has become a major difficulty, by UV polishing oil workers to make up for their deficiencies are often wasted time and affect the increase in the authentic rate. Therefore, whether UV light curing on non-absorbing electrostatic film materials can achieve technological breakthrough has been affecting the development of this product.
Second, the theory and practice of exploration is well-known: UV-curable curing ink can be used, referred to as UV ink, is composed of photopolymerizable oligomers and diluent monomers (resin binder), then add photoinitiator, coloring Agent etc. The linking materials are roughly divided into three major types: (1) reactive group polymerization type; (2) active group addition polymerization type of a polyenethiol curing system; (3) ionic polymerization type of epoxy resin.
The arrival of market internationalization and economic integration will surely be influenced by ecological policies. UV inks also face scientific theoretical breakthroughs and application technology innovations. It is no longer just paper, paper boxes, packaging papers, labels, metal foil composite paper, non-ferrous metals with oily or water-based, has become rely on molecules or ions Linear or indirect use of lithography, flexo, screen, gravure transfer printing, and even computer-assisted printing or non-absorbing printing media. With the aspiration of non-absorbing non-polar plastic materials in packaging, UV inks cannot cope with this market space.
In order to improve the packaging and printing environment, the equipment and facilities for photo-curing ink, photo-curing varnish are between 15KM and 64KM. In order to ensure the balance between printing speed and drying speed, people always arrange printing color sequence according to different pigment wavelengths in the color ink system: white ink - black ink - cyan ink - yellow ink - red ink, and according to the color hue To install or turn on the UV lamp (bubble) and adjust the light receiving distance, in order to ensure the high quality of the product and prevent the ink film from falling off, the printers are finally solving the problem by offset printing a UV coating.
Looking at the UV ink and UV coating on the market, the principle of drying is nothing more than photochemical reaction. The first condition is that the molecule must have enough energy photons to become excited (state) molecules. Just as every photon known to people can only activate one molecule; the same molecule can only absorb one photon at the same instant. Therefore, the theory is often interpreted as follows: After a molecule absorbs a photon, an electronic transition to a higher-order energy occurs, and the molecule undergoing an electronic transition is called an excited state (ie, a molecule). This excited state molecule not only releases energy but also releases energy. Returning to the ground state, it is also possible to transfer energy to other molecules or generate free radicals and then transfer the photosensitive polymer to polymerization or photocrosslinking and photobridges. Whether the ink system contains a photoinitiator, the purpose thereof is to cause a photocuring reaction of the UV ink system, that is, a result of a photochemical reaction, or a UV ink and UV coating that does not contain an initiator, which has been introduced in recent years. Its photo-curing is the result of the chemical reaction of the photopolymerization stage after the solvent cross-links the system into a network structure. The system contains UV absorbers. In absorbing natural sunlight and fluorescent sources, UV light can be converted into hardened crosslinked ink film structures.
We rigorously categorized and screened UV inks of the same application. We believe that the iodine lamp, which is a black light source with a cold light source, and a iodine lamp with a heat source, perform a recording test of the ink drying process. The former is superior to the latter in terms of safety. Because when the UV non-absorbing offset printing ink ink material after printing, subject to ultraviolet or visible light, the outer layer of its electrons are excited to jump to a higher energy level) in order to appear light absorption. The author applied different adjuvants to the unsaturation of Wuhan resin, Xi'an resin, and commercially available 191,196 resins and used the same colorant to perform tests. The test compares different molecules in different molecules, including different ones. Qualitative and quantitative analysis of organic compounds and metal complexes of saturated bonds, aromatic rings, and heteroelements. Although the UV region is between 200 and 400 nm, the visible region is between 400 and 800 nm, accounting for only 4% of visible light. It is this 4% effect on the photochemical reaction. (To be continued)