UV printing is a unique method of digital printing that uses ultraviolet (UV) light to dry or cure ink, adhesive or paint almost immediately after touching paper, aluminum, foam board or acrylic; in fact, as long as it fits on the printer, the technology can print on almost anything.
UV curing technology (a dry photochemical process) was originally introduced as a method of fast curing gel nail polish, but has recently been adopted by the printing industry to print on posters and brochures after passing through a digital printer.
The process is the same as traditional inkjet or laser printing, the only difference is the ink and drying process used and the quality of the products produced.
What are the differences between printing using UV and traditional printing?
Traditional printing uses solvent-based inks. They evaporate and release volatile organic compounds (VOCs) that are harmful to the environment. This method also generates and uses heat and the accompanying odors. It also requires additional dusting to aid the offset printing process and drying, which can take several days. The ink is absorbed by the printing medium, so the color in four-color looks washed out and faded.
The printing process is mainly limited to paper and cardboard substrates, so it cannot be used on materials such as plastic, glass, metal, foil or acrylic, like UV printing.
In UV printing, mercury/quartz or LED lamps are used for curing instead of heat as in thermal printing. The specially designed high-intensity UV lamp is distributed over the substrate closely following the special ink and cures immediately after application.
Since the ink changes from a solid or paste to a liquid almost immediately, there is no possibility of evaporation, so it releases no VOCs, toxic fumes or ozone, making the technology environmentally friendly, with a near-zero carbon footprint.
Inks, adhesives or coatings contain a mixture of liquid monomers, oligomers (polymers composed of very few repeating units) and photoinitiators. During the curing process, high-intensity light (wavelength between 200 and 400 nm) in the ultraviolet part of the spectrum is absorbed by the photoinitiator, which will undergo a chemical reaction (chemical crosslinking) and cause the ink, paint or adhesive to harden immediately.
Why choose UV printing for your print jobs?
It’s not hard to see why UV printing has outperformed traditional solvent and water thermal curing technology, and why it is expected to remain popular.
- This method speeds up production-meaning more work can be done in less time
- Wet ink droplets are eliminated, so there is no scratching or smearing, and because it dries almost immediately, it does not evaporate, so there is no loss of coating thickness or volume.
- The ink also has better physical properties, higher gloss, better scratch resistance, chemical resistance, solvent resistance and hardness, better elasticity, and the final product also benefits from greater strength.
- They are also more durable, more weather resistant and have greater resistance to fading, making them ideal for outdoor signage.
- The process is more cost-effective: more products can be printed with better quality and less waste in less time.
- The absence of volatile organic compound emissions means almost less damage to the environment, and this approach is more sustainable.
Choosing UV printing over traditional printing methods can be the difference between producing luxury items or a product from the heap.