Application of UV Printing Ink on Film (2)

Since absorption of light of different intensities tends to occur at different wavelengths, the formed absorption spectrum has a high sensitivity (photochemical reaction) degree, and it can be rapidly dried in the case where it is invisible and can be solidified, and it can be designed as a complete set. Fully automated (from offset to curing), also able to adapt to trace, trace analysis and dynamics studies - from light source to light intensity (voltage level not the same), from lamp type to output spacing The same); from the ink film thickness, including the amount of photosensitizer in the system) to the length of the ink pigment wavelength (the more transparent and thinner ink film, the shorter the wavelength; light energy, faster drying); from the substrate surface tension, Hydrogen bonding force, free energy to test its adhesion and so on.
In addition to the above-mentioned molecules being excited at a high energy level, it is also possible that under the action of a photosensitizer or an ultraviolet absorber, decomposition of photons (both photodecomposition processes), or activation of a part of a bond, generates an activating molecule (free radicals) ), Caused by the dual-polymerization or photocoupling reaction caused by coupling bridging, which has made the ink counterparts consensus. However, the use of non-absorbing polar UV inks may cause photon decomposition again, which will not be described here.
Achieve UV offset non-polar materials, to achieve adhesion fastness, change the low temperature characteristics, can flow normally and avoid the fluctuation of the way to work by varnishes, the author after research on the above issues found that: most ink and non-polar printing The hydrogen bond value, PH value, free energy value, and surface tension value of the material are too large to change, that is, the overall structure of the UV ink UV lacquer is not changed. At Jiangsu Yizheng Tianyang Chemical Plant, Tianjin Lisheng Chemical Factory, Songzi With the support of the resin plant and other units, boldly adopt grafting, compounding (mixing) technology, using "value engineering", "orthogonality" and "backward algorithm", adding 0.25% of the city with the support of Mr. Li Xiang of Qingdao. The LJJ·TM additive sold by the company was introduced into the UV ink system. After simple dispersion, in cooperation with the Qingdao China Daosheng Printing Co., Ltd., it can be attached to a solid and gratifying effect after starting the printing and printing. The process is simplified, the cycle is shortened, the adaptability is expanded, and the quality is improved. We have learned that: only by seizing the commanding heights of technology can we expand the printing and consumption space of non-polar flexible packaging printing media; only when occupying the beachhead of the market economy can we repeatedly emphasize that time is money and quality is life; only with high quality and low value Based on printing inks, we can seize the opportunity to occupy the beachhead of the market economy; only if we have no people, I have excellent people, and people are new to me, can we capture the latest scientific and technological achievements at home and abroad from the market information feedback for me Used.
Third, innovation and improvement of ideas 1. Green non-absorbing UV offset polar material inks, as the name implies, are based on different ink compositions and require adhesion, high flow, low cost, simple craftsmanship, and bright colors without the need for glossing.
We analyze the "ink manufacturing process" textbook (example formula design: 1 Polyol 25-45; 2 Polyol 20-40; 3 Propionic Acid 10-30; 4 Hydroquinone 0.05-0.2; 5-Toluene Phosphoric Acid 0.1- 2/Binder) Enumerated ink formulations (10% of colorant white 50-60%, color ink 15-25%; 20% of binder 40-70%; 3 adjuvant 0.01-20%) for analysis, not difficult to see The reason is that the system acid mixture is one of the causes of the photon decomposition process (molecular decomposition) under the action of a photoinitiator after the UV ink is formed into a film or becomes a source. In addition, we according to the current resin technical indicators: 1 viscosity 25-50 Pa · sec / 25 °C; 2 acid value of 20 or less; 3 color ≤ 10; ink technical indicators: 1 color near sample; 2 fineness 15-20μm; 3 flow Degree 20-35mm; 4 Coloring power 90-110%; 5 Viscosity 15-25 (32°C); 6 Impact strength (N·m) 29.4; 1 Photo-setting time SI-3, etc. It was found that the location of fluidity has not been adapted to the requirements of modern high-speed web offset non-polar carriers. For example, we have increased the styrene, which is an alkaline solvent, to improve its fluidity. However, after ultraviolet light curing, especially after the back exposure, the gloss is slightly poorer, and the second is that the friction ink film falls off into particles. The resin composition in the ink film system is small and overly brittle. On a large scale, the acid ink will increase the adhesion of the printing ink film. However, the emergence of the above-mentioned failures made us feel helpless for the moment, thus interrupting several years of research issues. In order to break through the set of academic theories and jump out of the cul-de-sac of the environment and conditions, we have set the priorities for unsaturated resins (general term for resin materials made by the condensation of monohydric or polyhydric alcohols and dibasic or polybasic acids). The formulas and processes for resin binders and pigments and dyes (see Table 1 for details) abandon traditional and practical loading methods and use compounding techniques to add additives. In the formulation, we designed an inorganic pigment, an organic pigment, an extender pigment, a metallic powder fluorescent dye, etc. in terms of colorant, and also from the price, color, light and shade, alkali resistance, abrasion resistance, and in particular the curing of the ink. Characteristics, storage stability, surface reflectivity and wettability considerations. (To be continued)

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