The stability of disperse red/reactive-red dye inks

Area of Science:

• Textile Chemistry
• Dye Chemistry
• Inkjet Printing Technology

Background:

• Inkjet printing requires stable colour pastes for consistent performance.
• Disperse dyes are crucial for textile coloration but can pose stability challenges in ink formulations.

Purpose of the Study:

• To investigate the stability of inkjet printing colour paste using CI disperse red 896.
• To determine the optimal additive concentrations for enhancing thermal, freeze-thaw, and centrifugal stability of the ink.

Main Methods:

• Formulation of colour paste with CI disperse red 896 and various additives.
• Analysis of thermal and freeze-thaw stability by measuring average particle size, viscosity, and surface tension.
• Characterization of centrifugal stability using specific absorbance measurements.

Main Results:

• Defoamers improve grinding efficiency without compromising paste stability.
• Optimal ink formulation includes 20-35 wt% colour paste, 6-14 wt% combined ethylene glycol and glycerol.
• Specific additive limits were identified: triethanolamine (<1 wt%), fatty alcohol polyoxyethylene ether (0.2 wt%), sodium dodecyl sulphate (<0.15 wt%), and polyvinylpyrrolidone-K30 (<0.7 wt%).

Conclusions:

• Optimized additive concentrations significantly enhance the stability of disperse dye-based inkjet inks.
• The study provides a quantitative guide for formulating stable and high-performance inkjet printing colour pastes.