Aluminium Sulfate

Aluminium sulfate is an aluminium-based mordant used in natural dyeing and other textile applications. It helps many plant dyes bond more effectively with fibers, improving colour development and durability.

It can be used in carefully tested mordanting processes for both protein and cellulose fibers. Because aluminium sulfate produces an acidic solution, recipes should be tested on a small sample before treating valuable textiles. Always follow a suitable recipe for the fiber and dyestuff being used.

Important distinction

This product is aluminium sulfate, not potassium aluminium sulfate—commonly known as potash alum or simply “alum.” Although both supply aluminium ions, they are chemically different and should not be substituted at the same weight without adjusting the recipe.

How to apply Aluminium Sulfate

Use approximately 8% WOF as a starting point; 8 g of aluminium sulfate for every 100 g of dry fiber.

Dissolve completely in warm water. Add the pre-wetted textile and heat gently for 45–60 minutes without boiling. Allow the bath to cool, then rinse lightly before dyeing.

For cellulose fibers such as cotton and linen, apply after a tannin treatment for improved fixation. Always test on a small sample and adjust the amount according to the fiber, dyestuff and desired result.

Supplied in a plastic container.

Net weight: 250 g
HS code: 2833.22