Simply put, solvent ink is a relatively inexpensive type of ink made to work in inkjet printers. In the world of ink the term solvent is used to mean any ink that is, in fact, not made with a water base.
Solvent ink's greatest application is in the printing of products that are to be used outdoors because of its ability to adhere to non-absorbent materials. Solvent ink also has the advantages of being fade proof, water proof and scratch resistant. These qualities enhance its usefulness in outdoor printing.
There are three parts to solvent ink: the carrier fluid, pigment and resin. Technically, solvent ink refers only to the oil-based carrier portion of the ink that keeps the other components in liquid form and once applied to a surface through jetting dissolves. Pigments used to produce color in solvent ink are applied in powder form to produce the best quality color and they are adhered to the printing materials by mean s of resin which both makes the color stick and protects it from damage.
Eco-solvent is a form of the non-water based ink that is made from ether extracts taken from refined mineral oil; the cognitive implication of the term "eco" which brings to mind the idea of an ecologically sound product is an inaccurate assumption when applied to this form of solvent ink because neither the material used in making it nor the creation process are ecologically conscious choices. Eco-solvents are also known as soft or mild ink; this form makes the creation of a reliable printer easier because of its slow dry time and the need for multiple heaters in the printer.
Aggressive solvent Ink, known too by hard or true solvent, is a fast drying form of the ink which uses a quickly absorbing solvent formula, allows prints to be made on surfaces that cannot handle a lot of heat. Aggressive solvent ink is also more scratch resistant and weatherproof than eco-solvent.
The cost for both the mild and aggressive forms of solvent ink are comparable when purchased in ink cartridges, but manufactures of printers made for use with the aggressive form have made bulk ink insert options that overtime save on ink costs in order to offset the fact that aggressive ink printers use 10 percent more ink than mild ink printers.