UV ink can be divided into two major categories in terms of application, namely: UV printing ink and UV printed circuit board ink. At present, UV printing inks used in the printing industry are widely applied in various printing fields such as offset printing, letterpress printing (including flexographic printing), gravure printing, screen printing and inkjet printing, while UV printed circuit board inks are mainly used for the printing of circuit boards (referred to as PCBS) in the electronics industry.
Offset UV ink
Offset printing uses UV ink, which eliminates the need for powder coating, facilitates the cleanliness of the printing environment, and avoids the troubles caused by powder coating in post-printing processing, such as the impact on varnishing and lamination effects. It can also be processed in a continuous line.
UV ink can also prevent ink from skinning, eliminating the worry when offset printing machines are shut down, and at the same time, it can increase the drying speed. Especially in packaging printing, it is often necessary to print large solid areas, which require a high density. Therefore, the ink application amount has to be increased. At this time, the drying issue of the ink becomes very important, and it often affects the printing production efficiency due to the ink's difficulty in drying. However, with the use of UV ink, this problem is easily solved.
UV ink is bright in color and has excellent wear resistance, making it highly suitable for printing on packaging and book covers.
UV ink does not penetrate during curing and can be printed on non-absorbent substrates, such as the printing of certificates and cards, which is an area that ordinary offset printing inks cannot reach.
In addition, offset UV ink is also widely used in the printing of direct mail, commercial forms and other documents. Abroad, the largest market for UV ink is offset UV ink.
2. Letterpress printing UV ink
Letterpress UV ink is mainly used for label printing and also for packaging printing, such as tube printing, etc.
In flexographic printing, especially in narrow-web flexographic printing, people pay more attention to less downtime, stronger wear resistance, and better print quality, etc. Products printed with UV ink have high dot clarity, small dot gain and bright ink color, which is a notch higher than those printed with water-based ink. UV ink has broad prospects for development.
At present, most flexographic printing machines are equipped with UV curing devices, and there are many types.
3. UV ink for gravure printing
In the field of gravure printing, UV inks have been selectively used, but the technology and cost have also been correspondingly improved. With the growing call for environmental protection and the increasingly strict requirements for the safety of packaging and printing products, especially food packaging, UV ink will become a development trend in gravure printing ink.
4. Screen printing UV ink
The advantages of UV ink in screen printing are very obvious. As it can only cure under UV light, it will not cause the troublesome problem of screen clogging on the screen plate. Moreover, it cures quickly, effectively solving the long-standing contradiction between screen clogging and ink drying speed that has plagued the screen printing industry.
The ink layer of screen printing is relatively thick and difficult to dry. Without a drying device, the printed matter is hard to stack and collect, and achieving high-speed printing is also very difficult. With UV ink, all of this is easily solved. For example, in CD printing, all UV inks are adopted, which improves the production efficiency.
In screen printing, the use of some decorative UV inks can produce some special effects and achieve the decoration of the surface of the printed matter. These special effects are difficult or impossible to achieve by other printing methods. Only screen printing combined with UV ink can realize them. At present, the commonly used UV inks include the following types: screen printing UV metal etching ink, screen printing UV wrinkle ink, screen printing UV coral ink, screen printing UV ice flower ink, screen printing UV refractive ink, screen printing UV crystalline pattern ink, etc.
In addition, at present, combining screen printing with gravure printing, flexographic printing, offset printing units, etc. to form a combined printing machine is a trend in the development of printing machines, and the screen printing unit must use UV ink.
5.UV inkjet ink
In addition to the UV inks mentioned above, a new type of ink - UV inkjet ink - is also highly worthy of attention. A new type of flatbed inkjet printer that adopts piezoelectric nozzle technology is strongly promoting the application of UV curing technology in inkjet inks. In addition, piezoelectric nozzle technology is now also used in hybrid printing machines and single machines. These new fields that use inkjet inks offer a development opportunity for UV inks and are expected to reach the current scale level of screen printing.
The superiority of UV inkjet ink lies in that it not only possesses the economic and technical advantages of traditional UV technology, but also has outstanding advantages in use and operation, mainly manifested in the following aspects.
(1) No volatile organic compounds;
(2) Low energy demand;
(3) Rapid curing;
(4) Suitable for a wide variety of soft and hard substrates;
(5) It will not cure before being exposed to UV lamps.
(6) It does not clog the nozzle and there is no need to clean the nozzle.
(7) The ink composition is stable;
(8) Good print quality and resistance, such as abrasion resistance, water resistance and light resistance;
(9) No ink waste.
Therefore, UV inkjet ink is currently developing very rapidly and is showing a strong trend of replacing traditional inkjet ink.
6.UV printed circuit board ink
In the production process of circuit boards, there is a part called a printed circuit board. The UV inks used for printed circuit boards mainly include: anti-corrosion UV inks (including electroplating resistance), solder mask UV inks, and character marking UV inks. All of them are printed by screen printing.
