UV inks

UV Inks

Find out the reasons why we print using UV inks!

For years the wide format digital printing market has been dominated by machines which use solvent inks. The solvent part of the ink controls the viscosity and assists in optimal drying onto the desired media substrate. The drying of these inks involves the evaporation of volatile solvent from the ink film, or the absorption of the ink into specially developed substrates.

The main ingredients of solvent inks are VOCs (Volatile organic compounds).  

Once the product has finished printing the solvents evaporate (i.e. when paint dries) giving off a very toxic odour. Although this eventually reduces to a minimal smell, it can take up to several weeks for solvents to completely evaporate.

To get an idea of how much evaporation take place this process removes about 35-40% of the delivered ink volume. In other words, you have to deliver 40% more volume to the substrate with water or solvent ink in order to achieve the desired colour density. Vapours of VOCs escaping into the air contribute to air pollution. Methane (part of VOCs) is an extremely efficient greenhouse gas which contributes to enhanced global warming.

This very problem has been noted not just in the printing industry but end line customers such as Marks and Spencer have expressed their intentions not to purchase any solvent printed graphics.

We at The UV Printing Company eliminate all of the above by using a machine that uses UV based inks. UV inks act like liquid plastic. As the ink is exposed to concentrated UV radiation, a chemical reaction takes place causing the ink components to cross-link into a solid. This is done by 2 UV lamps fixed to either side of the print head.

One of the most significant reasons for UV’s growth is concern over environmental issues. Due to the lack of volatile toxins evaporating, the process doesn’t harm any of our workers and all our prints can be used indoors with no nasty odours to worry about.

The reason for this is that UV inks do not dry in the air so no material is lost. This means nearly 100% of the delivered volume is used to provide colouration.

Due to the higher viscosities, UV inks tend to stay where they are placed. Dot gain is negligible resulting in exceptional image sharpness. For that reason, UV inks work well for printing fine line, process and vignettes.

In the past the fact that UV inks are thicker has been a problem but after a lot of development in the inks flexibility we now have inks that print and adhere to a vast range of substrates. These include banner PVC, vinyl, foam board, correx, metal, glass, plastic, wood and many more.  The use of white ink is a major plus when printing onto dark or transparent media.