UV inks and water-based screen printing inks will have a large market. Now most of the inks used in China are solvent-based inks. Solvent-based inks are volatile drying inks with slow drying time and 8 hours for natural drying. During the drying process, 60% of the solvent must be volatilized. This serious pollution, under the current slogan of "return to nature and environmental protection first", is not only restricted by the strict regulations of the government, but also opposed by the neighbors. The screen printing factory does not want to use it either. Therefore, it is inevitable for UV ink and water-based ink to occupy the screen printing market in the future.
One, screen printing ink (UV ink) market trend
At present, in terms of output and variety of screen printing inks, volatile drying inks are the mainstream. However, the output of UV inks is increasing year by year, and the increase rate is large. Its output exceeds that of volatile drying screen printing inks. It is only a matter of time. As the types of oligomers, prepolymers, and polymerization initiators in the raw materials of UV screen printing inks have increased, the application range of UV screen printing inks has become wider and can be suitable for screen printing on various substrates. Occupation rate will definitely increase.
1. Screen printing ink (UV ink) is suitable for various printing materials. Paper, coated paper, wood products, synthetic paper, polyvinyl chloride (PVC(4565, 20.00, 0.44%)) 1 propylene (PMMA), acrylonitrile-butene-styrene terpolymer, acrylonitrile-styrene Copolymer, styrene (PS), ABS, polycarbonate (PC), polyester (PET), polyurethane, treated polyethylene, treated polypropylene, plastic (7885, 15.00, 0.19% ) Coating surface, polyethylene plastic (PE), woodware coating surface, coated metal plate, glass (869, -14.00, -1.59%) ceramics, thermosetting resin.
2. Screen printing ink (UV ink) has strong function and performance. Screen printing ink (UV ink) is suitable for high-quality, diversified and special-shaped products that require special processing.
①Physics: LCD screen, anti-corrosion soldering; electrical insulation, conductivity, electroluminescence, magnetism, etc.; thermal temperature foaming, temperature display, pearlescent, fluorescence, night crystal, thermal transfer, etc.
②Chemical and medicinal products include corrosion, ethanol peeling, etc.; biochemical products include antibacterial and antifouling, etc.; absorption, adsorption, and reaction include water resistance, oxidation and corrosion.
③Surface decoration: crystal glue, anti-metal etching, matte wrinkles, non-glare, mirror metal, etc.; for three-dimensional, thick film printing, braille, crystal patterns, wrinkles, fragmented graphics, coral-like patterns, etc.
2. Water-based printing ink market trends
Among the volatile and drying printing inks, the water-based printing inks developed in the 1980s are highly valued because they are environmentally friendly. Water-based printing inks once attracted people's attention at the beginning of the development, but they have not been popularized because of the poor water demand of the stencil and the problems of wrinkling caused by the paper's absorption of water when printing on paper. After entering the 1990s, the above-mentioned problems were gradually solved. With the advent of new water-based printing inks using urethane emulsions, their varieties are also increasing.
From an objective analysis, because the function, use, price, equipment and supply of (water-based printing ink) are better than those of screen printing ink (UV ink), traditional printing inks will gradually disappear in the screen printing ink market in the future , Replaced by water-based ink and UV ink, and finally water-based ink completely occupied the market. Commercialized water-based inks have already complied with the principles of simplicity, practicality and economy. The three previous shortcomings have now been overcome.
1. Drying problem of screen printing water-based ink.
The biggest disadvantage of water-based printing inks is that the drying is slower than solvent-based printing inks. In theory, 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, the composition of water-based printing inks is now completely improved. ① First, reduce the water content of water-based printing inks from 70% to 30%. ②The water-based printing ink is ultra-micronized so that the water-based ink, which can only be printed with a 150-mesh screen, can be printed with a 300-mesh screen. In this way, the printed film becomes thinner and the drying speeds up. ③On the premise of not hindering the printing effect, reduce the viscosity of the water-based printing ink, reduce the surface tension, promote the capillary phenomenon, and improve the effect of evaporation drying and penetration drying. ④The most important thing is to have a high-performance infrared dryer. Because infrared radiation is radiant energy, it has penetrating power and can directly interact with the molecules in the printing ink. It generates heat at the same time inside and outside, which promotes instant drying. Nowadays, water-based printing inks are used for color printing, and the color and color are dried instantly, 150℃ As long as 5s. This drying speed is almost as fast as screen printing ink (UV ink).
2. Adhesion of water-based printing ink
In the past, water-based printing inks were effective on absorbent objects (porous objects) such as cloth (cotton, linen, wool, silk, polyester, nylon and its blended fabric), paper (paper, cardboard), wood (wood, wood, plywood) , Leather (leather, artificial leather), etc. The adhesion is good, but it is difficult to adhere to the hard surface of the printing material. Now because the fixing agent of water-based printing ink is made of acrylic, polyester, and polyester superimposed resin, its all-round adhesion function is suitable for non-absorbent substrates, smooth and hard substrates and objects that were difficult to adhere in the past. Very good adhesion. Such as water-repellent 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.
3. The problem of fully water-based printing inks
Although the water-based printing inks in the past are already water-based, most of them are added with 10%-15% solvent, the purpose is to improve the flexibility, vividness of the printing ink and prevent bleeding. The current water-based printing inks can overcome the above problems and are all water-based printing inks.
The development of water-based printing inks has become a hot topic among screen printers. Because the country has regulations on environmental protection, screen printing practitioners have awakened themselves and have turned to water-based printing inks instead of solvent-based printing inks for their own health. Neighbors of the screen printing factory, as long as there is a little peculiar smell, they will report to the environmental protection department by phones; when receiving orders from export traders such as toys, garments, furniture, curtains, etc., they often indicate the use of non-toxic printing inks; consumer purchases When buying shirts, you also learn to feel it with your hands to see if it is printed with water-based printing ink. Customers should also ask if it is printed with water-based printing ink when subscribing. The other reason is that all the pre-press of screen printing can be processed by computer. From design, text, pattern, combination to four-color film output, urgent items can be delivered within one hour, screen-making (four-color plate) is picked up on the same day, high-performance four-color screen printing machine, high-performance infrared instant dryer are available The supply creates conditions for the use of water-based printing inks.