1. Phosphate system: the representative product of the phosphate system substitute alkali is Alkaflo developed by Sybron. The Morran patent gives specific methods for this system: different raw materials can be mixed to make alkali liquor of different pH values. High-pH alkali liquor mainly contains tripotassium phosphate, potassium hydroxide and sodium hydroxide (sodium hydroxide in small amounts to improve temperature stability of the liquor; it can be omitted). Low-pH alkali liquor mainly contains sodium dihydrogen phosphate and phosphoric acid. By mixing high- and low-pH liquors in different proportions, a series of liquors of different pH values can be obtained. Adding borates and ethanolamines improves the buffering capacity of the system; ethanolamine can be mono-, di-, tri-ethanolamine or their mixtures.

Typical formulas: for high-pH liquor, tripotassium phosphate 20-50%, potassium hydroxide 2.5-20%, sodium hydroxide 0.4-7% if selected, ethanolamine 4-8%, borax pentahydrate 4-8%; the balance is water.

2. Use and comparison: substitute alkali replaces soda ash in reactive dyeing, giving a more stable pH curve, more even fixation, and easier dissolution and dosing. Compared with soda ash, it reduces salt dosage in some processes and improves levelness and reproducibility. The dosage must be adjusted according to the dye brand and depth; confirm with a small sample before production.

3. Notes: substitute alkali contains strong alkali components; store and handle safely. Keep the dosing system clean to avoid blocking.