UV ink, water-based screen printing ink will be a big market, now most of the ink used in China is solvent based ink. Solvent based ink is volatile drying ink, drying time is slow, natural drying takes 8 hours. In the drying process, 60% of the solvent will volatilize. Under the slogan of "back to nature and environmental protection firstly", this serious pollution is not only restricted by the strict laws and regulations of the government departments, but also opposed by the neighbors, and the screen printing factory does not want to use it. Therefore, it is inevitable that UV ink and water-based ink occupy the screen printing market in the future.
At present, from the output and variety of screen printing ink, volatile dry ink is the mainstream. However, the output of UV ink is increasing year by year, and the growth rate is large. It is only a matter of time before the output of UV ink exceeds that of volatile drying ink. Due to the increase of the types of homopolymers, prepolymer and polymerization initiator in raw materials of UV ink, the application scope of UV ink is more extensive, which can be suitable for screen printing of various printing materials, and its market share will certainly increase.
UV ink is suitable for all kinds of substrate paper, coating paper, wood products, synthetic paper, PVC-1 propylene (PMMA), acrylonitrile butene styrene terpolymer, acrylonitrile styrene copolymer, styrene (PS), ABS, polycarbonate (PC), polyester (PET), polyurethane, treated polyethylene, treated polypropylene, plastic coating Surface, polyethylene plastic (PE), wood products coating surface, coating metal plate, glass ceramics, heat hardening resin.
UV screen printing ink has strong functional performance. UV screen printing ink is suitable for high-quality, diversified and special-shaped products.
1) Physical properties: liquid crystal display screen, anti-corrosion negative welding; electrical insulation, electrical conductivity, electric field luminescence, magnetism, etc.; thermal temperature foaming, temperature indication, pearlescent, fluorescence, night crystal, thermal transfer printing, etc.
(2) The chemical and medicinal ones are corrosion and ethanol stripping; the biochemical ones are antibacterial and antifouling; the absorption, adsorption and reaction are waterproof and oxidative corrosion.
(3) Surface decoration: crystal glue, anti metal etching, lusterless wrinkles, non strong light, mirror metal, etc.; for three-dimensional, thick film printing, Braille, crystal pattern, wrinkles, broken pictures and texts, coral pattern, etc.
Among the volatile drying inks, the water-based inks developed in the 1980s have attracted much attention due to their environmental benefits. At the beginning of the development of water-based ink, people once paid attention to it. However, due to the poor water demand of the template, and the problem of easy wrinkling caused by the absorption of water in paper printing, it has not been popularized. In the 1990s, the above problems were gradually solved. With the advent of new water-based ink with carbamate emulsion, its varieties are also increasing.
The biggest disadvantage of water-based ink is that the dryness is slower than the solvent type. Theoretically, the evaporation energy of water is 4-5 times larger than that of oil. How to improve the dryness is a comprehensive problem. After years of research, now the composition of water-based ink is completely improved. First of all, the water content of water-based ink was reduced from 70% to 30%. Secondly, to make the water-based ink superfine, so that the water-based ink which can only be used for 150 mesh screen printing can be used for 300 mesh screen printing. In this way, the printing film becomes thinner and the drying is accelerated. The third is to reduce the viscosity of water-based ink, the surface tension and promote capillary phenomenon, so as to improve the effect of evaporation drying and osmotic drying. Fourthly, the most important point is to have a high-efficiency infrared dryer. Because infrared ray is radiation energy and has penetrating power, it can directly interact with the molecules in the printing ink, and the inside and outside are heated at the same time to promote instant drying. Now water-based ink is used for color printing, and the instantaneous drying between colors is only 5 seconds at 150 ℃. This drying speed is almost as fast as UV printing ink.
In the past, water-based ink on absorbent objects (porous objects) such as: cloth (cotton, hemp, wool, silk, polyester, nylon and its blended cloth), paper (paper, cardboard), wood (wood, plywood), leather (leather, artificial leather) and so on, is connecting well, but it is difficult for the hard surface of the printing materials. Now because the water-based ink fixative is the use of acrylic, polyester, polyester coincidence resin, its all-round follow-up function on non absorbent substrate, smooth and hard surface of the substrate and the past difficult objects have excellent adhesion. Such as water cloth, synthetic paper, thick canvas, rigid PVC, PVC, stickers, PVC cloth, artificial leather, acrylic, ABS, as, pet, PS, glass, hard aluminum foil, stainless steel, etc.
Traditionally, although water-based inks have been water-based, most of them are added with 10% to 15% solvent to improve the softness, brightness and prevent penetration. Now the water-based ink has been able to overcome the above problems, is all water-based printing ink. In Europe, water-based UV ink has long been used for screen printing large-scale road signs and posters. The reason why water-based ink and water-based UV ink are used more and more is mainly affected by environmental regulations and requirements to improve the working environment. Of course, there is another reason, four-color screen printing, dot reproduction is very good. Therefore, in the future, in order to play the advantages of water-based ink, the rapid expansion of the water-based ink market is inevitable.