UV ink and UV coating oil in the application of experience

With the rapid development of the modern packaging and printing industry in the direction of fast, multi-color one-time printing, UV inks and UV coatings have become the new darling of packaging and printing materials. However, with the application of time, applications continue to increase, people have put forward newer and higher requirements for these products: not only need to quit on the printing machine, but also can be quickly dried after printing; not only the low cost of materials , but also high gloss; not only have to store a long period of time, but also printing, roll coating and good adhesion.

At present, there are few that can meet the above requirements at the same time. However, operators in the packaging printing industry generally care about the adhesion of the printing ink film and the roller coating film, and secondly, they can flow at low temperatures without agglomeration.

We know: Whether it is UV ink, or UV Varnish, packaging and printing plant is afraid of the high temperature and humidity in the season; second is that the moisture content of the substrate exceeded. Because the above-mentioned workshop environment and the substrate are easily removed by the initial inspection (tape paper) after printing or polishing, the ink film or the film is pulled off and returned by the user. For example, the author found in front of the “Shuanghui” Group in Luohe, Henan Province: The group’s ham sausage carton packaging was sealed with adhesive tape. When the consumer peeled the tape, the packaging (ink and varnish) on the packaging sealing part was The unfavorable phenomenon of block pulling down reduces the quality of the packaging product (face) view and directly damages the brand image of the company. Another example is the Nanjing Gold Foil Group printing ink on the Wuhan Golden Dragon Cigarettes. When it is automatically labelled at high speeds of 140-160°C, it is often difficult to label the labels in the continuous labeling process, that is, it is not resistant to high temperature or cut-off printing. Graphic blocks.... This not only affected the reputation of the gold foil group with a certain degree of know-how, but also gave the user an unnecessary scrap rate. The kind of technology transfer products that use so-called elite schools and scientific research units—ignoring the increasingly maturing of China's packaging and printing industry—quality control. Still according to this book, accustomed to printing to follow the performance of ink materials, resulting in the production of UV inks and UV coating products can not keep up with the pace of development of the times, leading to the production of some consignment companies, printing ink scrap, even a large number of scrap, and even Closed and closed down. This kind of theoretical "brows fly" and technical mistakes can not be measured by money, can not use a few packaging and printing companies to scrap the material to calculate the cost of production. The extremely unfair economic burden brought endless suffering to some enterprises.

It was with curiosity that the author learned and observed from Yiyang, Hunan, Pudong, Shanghai, Zhangjiagang, Jiangsu, Wuxi, Xinxiang, Henan, Xiangyang, and Qingdao, Shandong. After combining experiences of previous years, he visited seniors in the printing industry successively. Its traces, philosophical exploration of the truth, the text will be its heart. From the photocuring resin or prepolymer to the amount of cross-linking agent, from the different brands, technical parameters and actual proportions of photosensitizers to polymerization inhibitors, it was considered that some manufacturers have neglected the role of cross-linking agents (because people It is known that an ideal cross-linking agent is also an ideal reactive diluent, which not only has good miscibility with the resin, but also can dissolve and dilute the unsaturated polyester and resin, lower the viscosity of the ink and varnish system, and improve the ink and light. The fluidity of the oil. And can participate in the photo-curing reaction, so in their formulations are often less, resulting in poor ink flow and the agglomeration of varnish, do not engage in freezing ... .... The second is that the general amount of photosensitizer is too large, and it is erroneously recognized that photosensitizers can increase the speed of photo-curing. Actually, the amount used is not only not increasing the speed of photo-curing, but also increasing the production cost. Excessive, but will reduce the UV ink or UV coating conjunctival strength and so on. Some insights have been realized. In the field, new material preparation and production process adjustments, trials, comparisons of application methods, light intensity and light energy recording during the photochemical reaction process, curing speed and temperature and humidity control of the workshop environment, and substrate pH and moisture content ( 1,2,3,5,6,7,8) Comparison found: whether it is alcohol sol or PVC primer substrate for the substrate of the water content is controlled at 3 is appropriate, so said printing UV ink and roller coating UV varnish has poor fluidity and agglomerate adhesion, which is related to moisture content. As the main source of UV inks and UV varnish, there are less cross-linking agents and too many photosensitizers in formulation design. . As a packaging and printing company operator, one is to replace the new UV ink and UV varnish, and the second is to add JS-PPH (302) of Shanghai Jinshan Chemical Factory with 3-6 temporarily in the ink or varnish. Membrane auxiliaries (Because the alcohol ether mixture is an environmentally friendly coalescent additive, the dosage is 10-20 than the ordinary common filming auxiliaries, and can effectively improve the freeze-stability of printed UV inks or UV varnishes. High gloss of ink film or film after photocuring) or addition of 0.2-0.5 JS-F4011 adhesion promoter (as the introduction of silane compounds, ink film of UV ink after printing and film of roller coated UV adhesive Antioxidation, anti-yellowing, accelerated pigment dispersion, sizing and leveling, inhibition of floating color, hair growth and other undesirable phenomena in the film formation process is suppressed) or adding 5-15 CH3COOC2H5 (because the material is very widely sourced, The effect is very obvious. It can destroy the printing ink layer and the bottom oil adhesive layer in a very short time, and achieves slightly soluble mutual adhesion, promotes the packaging and printing graphics or the adhesion fastness of coating oil, and can guarantee the packaging and printing ink. The adhesive strength of ink film and varnish film has been fundamentally improved.

Through the practice of improving the quality of packaging and printing products, we see that: Regarding the research and development of green products, we cannot look at its technical content and the number of products. We must implement new product marketing and applications, and we must not look at actual sales prices and application areas. Instead, we should Look at the expected benefits of the packaging company's technology in the future. In a word, we must use the eyes of the market to judge the behavior of packaging and printing companies in the competition.