Digital printing ink can be distinguished according to the solvent. They can be divided into two types: one is water-based ink, and water and water-soluble solvent are the main components of the dissolved color base. The other is an oil-based ink, which uses a water-insoluble solvent as a main component of the dissolved chromophore.
According to the material, it can be divided into two types. One is dye-based ink, currently, most inkjet printers are used. The second is a pigment ink, which is a pigment based ink.
What we need to pay attention to is that some pigment inks may be water-based inks or oil-based inks, but water-based inks and oil-based inks are absolutely not allowed to be mixed in the same print head in terms of their properties and the actual requirements of the printer.
There are five main factors affecting ink quality: dispersant, conductivity, pH, surface tension, and viscosity.
Dispersant: It is a kind of surfactant. Its function is to improve the physical properties of the ink surface and enhance the affinity and wettability of the ink and sponge. Therefore, the ink which is generally stored and transmitted through the sponge contains a dispersing agent.
Conductivity: This value is used to reflect the level of salt. For better quality inks, the salt content should not exceed 0.5% to avoid crystal formation in the nozzle.
PH value: refers to the liquid pH, the more acidic the solution, the lower the PH value, conversely, the more alkali the solution, the higher the PH value. To prevent ink from eroding the nozzle, the pH should generally be between 7 and 12.
Surface tension: can affect whether the ink can form droplets. The better quality ink is low viscosity and high surface tension.
Viscosity: the resistance of the liquid flow, the viscosity of the ink is too large, which will interrupt the ink supply during the printing process; the viscosity is too small, and the ink head will flow during the printing process.
The digital printer ink can be stored for two years under normal room temperature. It needs to be sealed for storage, avoid direct sunlight, and the temperature should not be too high or too low.