Several indicators of ink

1. Interfacial tension:

In units of mN/m. Unlike the so-called "surface tension", the interfacial tension includes the surrounding medium, for example, air is mostly used as the medium during the test. This parameter affects the following performance.

a. Print edge sharpness b. Ink permeability in paper and other media

Ink Flow in the Ink Cartridge Range of common ink interfacial tension values: Epson and Canon black and color inks <34 mN/m @ 20°C, HP and Lexmark black inks> 50 mN/m @ 20°C, HP and Lexmark Color ink < 34 mN/m @ 20°C.

Ink with low interfacial tension: ink droplets are small, ink will penetrate deeper into paper or other media. Ink with high interfacial tension: large droplets, low permeability to media. However, excessive interfacial tension can cause large amounts of foam , This ink is not qualified.

2 Viscosity:

Viscosity affects the following properties of the ink:

a. Edge sharpness of the printed font and ink permeability in paper and other media b. Fluidity of the ink in the cartridge (especially ink cartridges with sponges, such as HP color cartridges and Lexmark black/color cartridges)
c. Blocking of the ink flow (if the viscosity of the ink is too high, the ink flow will be completely blocked).

3. pH value

a. If the pH is too low (acidic), the ink will corrode the ink cartridge b. If the pH is too high (alkaline), additional salt will be generated to reduce the life of the cartridge (corrosion) and increase the conductivity c. Good ink stability, ink pH must be comparable to the desired pH of the dye
4. Conductivity:

In ink, the conductivity value is used to reflect the level of salt content. This parameter is affected by the following factors:

a. Salt in the water/ink (eg sodium chloride) can damage the ink cartridge or even render it inoperative b. The ionicity of the dye does not cause damage to the cartridge as salt does.

In general, the salt content should not exceed 0.5% and the conductivity should be less than 10000us/cm; to avoid crystallization at the nozzle.

5. Density and granularity:

This parameter is affected by the composition of the ink.

a. The density of the dye ink is mostly between 1.00 and 1.03 b. The density of the pigment ink is approximately 1.04. The particle size of the ink should be less than 0.2 um.