Black pigment ink for ink-jet printer and method for preparing the same

Abstract

The invention provides a black ink for ink-jet printers, which comprises 10-30% of carbon black, 0.1-1.25% of amphiprotic polymerized substance, 0.1-1.5% of levelling agent, 10-30% of wetting agent, 0.05%-0.5% of defoaming agent and deionized water, 20-33% of carbon black dispersion liquid, 0.05-2% of surface active agent, 5-50% of humectant, 0.1-2% of pH regulator, 0.5-2% of drier, 0.1-0.5% of preservative agent, 0.1-0.5% of mold preventive, 0.01-0.5% of chelating agent, 0.1-2% of resin and deionized water.

Description

Technical field: [0001] The invention relates to the field of pigment black ink for inkjet printers. Background technique: [0002] With the continuous development of computer technology and digital technology, inkjet printers have been accepted by more and more users as a very useful output device, and the penetration rate has also increased day by day, making family and office affairs more convenient and convenient. Efficient and standardized. At present, the mainstream in the inkjet market is still dye-based ink, which has the characteristics of bright colors and high reduction rate, but its poor waterproof and light resistance make its application limited; while pigment ink has excellent waterproof and light resistance. Performance, because the pigment itself is waterproof, so the printed or spray-painted products are also waterproof. At this point, black ink is more prominent. Among inkjet printer inks, black ink has the largest market share. Even if the printing su...

AI Technical Summary

Problems solved by technology

[0003] Carbon black is the most important black pigment. Inkjet colorants basically use carbon black, and carbon black is used as a colorant. There is such a problem. Because its surface is lipophilic, its dispersibility in water is poor. The nozzle will be clogged, condensate and heterogeneity will be generated during storage, so that it cannot be used, so it is necessary to obtain a dispersed and stable carbon black solution by adding a dispersant or other methods

[0004] The most common dispersing method is to disperse carbon black through traditional surfactants under the action of dispersing equipment. Although this method is simple and easy, there are the following limitations due to the molecular structure of the dispersant: (1) Hydrophilic groups The combination on the surface of less polar or non-polar particles is not firm, and it is easy to desorb and cause re-flocculation of dispersed particles; (2) The lipophilic group does not have sufficient carbon chain length (generally no more than 18 carbon atoms) , so it cannot produce enough steric hindrance effect in the dispersion system to play a stabilizing role. If the obtained dispersion is used for inkjet ink, it will appear delamination and agglomeration for a long time, and it will block the nozzle after it is put on the machine.

Dispersion with resin has the disadvantage that since the resin dispersant is combined with the surface of carbon black in order to exert its effect, the amount of resin added must exceed the amount combined with the surface of carbon black, otherwise a good dispersion effect cannot be obtained

In addition, due to the oxidation treatment at a high temperature of 100 ° C for up to 12 hours, there will be corrosive acids soluble in water, which is very unfavorable for the nozzle