Stabilization of pigments in ink

Since pigments are, by definition, insoluble in water, it is not individual molecules that are surrounded by water particles, but larger aggregates. The finer the pigments are ground, the smaller they are. Nevertheless, even the finest pigment particles sink to the bottom if you wait long enough. The water molecules have no way of "holding" the pigments, since they are chemically too different (water polar, pigment non-polar).

Wetting agents (surfactants) now have the property of combining polar and non-polar groups in one molecule. The head group is usually polar, and the tail group non-polar. If such a surfactant is dissolved in water, so-called mycells are formed. These are spherical structures in which the tails point inward and the heads outward. This allows the water to dock onto the heads. The non-polar "interior" then holds non-polar substances that are otherwise not soluble in water, e.g. our pigment particles. Through clever choice of surfactants, it is possible to keep the pigments in suspension for quite a long time. However, such an ink is sensitive to low temperatures, for example, because the mycells are destroyed in the cold.

Refill ink Brother LC-223, LC-227, LC-229, LC-12E black pigmented
Refill ink Brother LC-223, LC-227, LC-229, LC-12E black pigmented
Refill Ink Selection, a selection of the best inks of the manufacturer OCP.
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Refill ink Brother LC-22UBK, BT6000BK, DCP-J 785, MFC-J 985 black
Refill ink Brother LC-22UBK, BT6000BK, DCP-J 785, MFC-J 985 black
The colour was developed by Octopus Fluids, specifically for Brother DCP-J 785, MFC-J 985.
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Ink for Canon PGI-525, 550, 555, 570, PG-540, 545, 510, 512 pigm. black
Ink for Canon PGI-525, 550, 555, 570, PG-540, 545, 510, 512 pigm. black
The colour was developed by OCP specifically for Canon Pixma PRO 100 photo printers.
Content:   ( € /  )
Octopus Refill Ink for HP 336, 337, 338, 339, 350, 350 XL pigmented black
Octopus Refill Ink for HP 336, 337, 338, 339, 350, 350 XL pigmented black
Test inks according to DIN 53126 are produced by Octopus Fluids® and tested according to DIN EN 14370, DIN 19268 and DIN 51562.
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