There are so many choices of inks on the market today, how do you know what ink is best for printing on your particular substrate? It is important to know that inks such as eco-solvent or aqueous inks do not work well with certain substrates, yet provide decent quality prints at a cheaper price when paired with the correctly.
This has made aqueous inks, solvent inks and UV cure the most commonly used inks in the printing industry. Aqueous inks mix the pigment or dye with water as a base, solvent inks use oil or alcohol and UV cured inks solidify when exposed to UV light.
These inks use water as a base and are therefore polar, which makes them great for printing on substrates such as paper. These are the type of inks that are typically used in a non-industrial or commercial setting and found in most household printers. A selling point for this type of ink is tat it is environmentally friendly and does not contain harmful materials, and can produce a wide color gamut with high definition.
There are two types of dye and pigment based aqueous inks:
Dye based inks are dissolved in water, when the water evaporates only the color is left on the page. Some negative features of this ink are that is tends to soak the paper and is not highly waterproof or resistant to light. This ink is ideal for normal office use applications that will not be exposed to outdoors or moisture. For any applications that require long lasting color and definition, pigment ink is recommended.
Pigment inks are very small particles dissolved in water and when the water evaporates the only the pigments are left allowing them bond to the paper. These types of inks have slightly more water resistance then dye based inks, since the particles do not reabsorb the water as quickly. It has a slightly lower level of resolution then dye inks, but it is quickly rivaling the resolution of dye-based inks. It has much better color retention over time and is recommended for uses where longevity is key.
Instead of having the particles suspended in a water-based solution, solvent inks use a chemically enhanced liquid, which provides a superior bonding, color durability and water resistance. They are typically only found in industrial or commercial printers and work great for every day, long-term production. The solvent can penetrate the protective coating on solvent canvas and paper, therefore the ink lies underneath the coating, which eliminates the need for a top coating. A wide variety of different solvent liquids exists within the filed of solvent inks, falling within either eco-solvent or solvent ink.
a)Eco-Solvent (Mild Solvent):
The solvents used in these materials are far less toxic then those used in traditional solvent inks, but until recently fell behind the chemical enhancement that made solvent inks the clear winner. It is able to have the color resolution and water resistance that all solvent inks offer, while also able to be used indoors. When compared to solvent inks the only real disadvantage is that it cannot match the range of surfaces that solvent inks can print on.
b) Solvent (Aggressive Solvent):
These inks use toxic that they provide the best bonding between ink and canvas. It is perfect for outdoor scrim or vinyl banners or any non-traditional materials that you would be printing on. Solvent ink is the most widely used ink that is required to have superior environmental resistance or prints expected to last large amounts of time.
c) UV Cured Ink:
UV Cured Ink is a newer technology that does not have a liquid based solvent. Instead is remains a liquid until it is exposed to UV light at which point it rapidly solidifies. This makes it very easy to use, as the ink is disposed on the substrate through the printhead and a UV light is ran over it to dry. This offers many advantages for a printer: faster production, ink doesn’t clog up the printer (as it cannot dry without UV light) and you can easily see problems in the printing process as the ink is instantly dry.
One of the main disadvantages of this process is the limited variety of substrates to print on. In addition, the ink cannot be opaque, as the UV rays must reach across the substrate in order for it to dry. It also only works on hard substrates.
d) Latex Ink:
Latex Ink systems are a newer technology that, according to HP, is superior to eco solvent inks and comparable to mild solvent inks, without using any of the toxic materials. This means that latex ink systems can be used indoors without any fear of the toxic chemicals that are found in solvent inks and used in similar uses. In addition, they also come out ready to varnish and solvent inks require a drying system. As this is the newest major form of inkjet printing, there are still going to be regular advances in the field and increasing its effectiveness.