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Soda ash
$4.40 – $8.00
Used with fibre reactive dyes as a colour FIXATIVE. Soda ash raises the pH and allows the dye to bond with the fibre. Generally used only with cellulose (plant) fibres such as cotton or flax. Also known as washing soda or sal soda, though this is a more pure form that the washing soda sold in supermarkets.
Also sometimes used in natural dyeing to create more alkaline conditions, and thus altering the colour with certain plants. Extensively used for indigo vat dyeing.
TO USE: Follow dye manufacturer’s directions for amounts and timing.
Dispose of spent dyebath in the usual way, most likely down the drain.
CAUTION: Wear a mask when handling powders. Wear gloves, can be a skin irritant.
Related products
Thiourea Dioxide
Sometimes called Thiox. Used in the INDIGO VAT dye process, thiox removes oxygen from the vat solution, allowing the indigo to work its magic. Thiox is also a colour remover, and is used for that purpose in discharge dyeing, to create white patterns on a coloured background.
TO USE: Follow the specific indigo vat recipe, for amounts and timing.
Dispose of spent dyebath in the usual way, most likely down the drain.
Thiourea dioxide has a shelf life but it's longer than some things you read might indicate. If the powder has a distinctive yellow look, it has probably oxidized to some degree and may no longer be effective. Store in a cool, dry place out of the light i.e. in a cupboard in the house, not out in the garage.
CAUTION: Should be done OUTDOORS ONLY or with excellent ventilation. Avoid breathing fumes. Wear a mask when handling powders. Wear gloves.
Titanium oxalate
Used as a MORDANT in natural dyeing, which allows the plant pigments to bond with the fibres.
Titanium is used both on protein and cellulose fibres, giving vibrant orange and gold tones when dyes contain tannins. As a mordant, this is relatively new and not much information abounds in books or even online. It may be the closest thing now available to replace chrome, which nobody much uses any longer.
TO USE: weigh the dry fibre or yarn. Calculate mordant required for 8 to 15% WOF (weight of fibre). Dissolve in hot water. Fill pot with sufficient water for the fibre to move, add titanium and stir. Enter fibre. Bring to 180-200 degrees F and hold 1 hour. Stir yarns frequently. Cool, remove fibre and wash well. Dye immediately or dry for later.
Some interesting results are being produced doing Eco-Printing on fabric, using Titanium as a mordant.
We cannot seem to find much information on safe disposal of a Titanium mordant bath. Nothing we've found indicates it to be particularly toxic or harmful to plumbing or sewer systems, but to be on the safe side it may be best to dispose of this outdoors on a gravel driveway or similar place.
CAUTION: wear a mask when handling powders. Wear gloves when rinsing or handling wet yarns. BEST DONE OUTDOORS or with very good ventilation. Avoid breathing fumes.
Citric acid
Used in place of vinegar, as a MORDANT on protein fibres when working with acid dyes or food colouring. Many production dyers switch to citric acid because buying jugs and jugs of vinegar gets too expensive, and vinegar makes your house smell like a pickle factory. Citric acid is odour free!
TO USE: dry crystals may be easily weighed at 5 to 8% WOF (weight of fibre). Follow dye instructions for the recommended acid amounts. Just as with vinegar, the point at which you add the acid to the dyepot can make a substantial difference in the end results. Same goes for hand painting and other methods.
TO MIX A VINEGAR SUBSTITUTE: add 200g (approximately 1 cup) of citric acid crystals to 4L of hot tap water in an empty vinegar jug. Cap and shake well until dissolved. This makes a 5% solution that can be measured and used exactly the same as for vinegar in your dye recipes.
Dye solutions containing citric acid may be safely disposed of down the drain (other than septic systems). Some dyers use baking soda to first neutralize the spent dyebath.
CAUTION: wear a mask when handling powders. Wear gloves when handling citric acid powder, as it can cause skin burns. Avoid breathing fumes (just as with vinegar): dye in a well ventilated area.
Iron sulphate
Used as a MORDANT in natural dyeing, which allows the plant pigments to bond with the fibres.
Iron darkens or "saddens" colours. It takes only a tiny amount to do this, and one must be careful with iron: too much will harshen or damage fibres. If you use iron with any regularity, consider having a dedicated pot for this purpose, as it sticks to pot surfaces and will affect the colour of future dyebaths. A chipped enamal pot is perfect.
Used mainly on protein fibres such as wool, alpaca, silk. Although it can be used as a premordant, most natural dyers use iron to alter the colour at the end of the dyeing process. If you prefer to premordant, follow the usual steps using iron at 6% WOF.
TO USE: Weigh fibre before wetting. Dye in the bath of your choice, with or without an alum premordant. Calculate iron mordant required for 2% WOF (weight of fibre). Dissolve iron in hot water. Remove fibre from warm dyepot, stir in dissolved iron and re-enter fibre. Simmer for 5 minutes, cool then wash and rinse well.
Spent mordant solution may be safely disposed of by pouring in the garden. Iron sulphate is a common soil amendment in agriculture and horticulture.
CAUTION: wear a mask when handling powders. Wear gloves when using iron, as it stains skin easily. BEST DONE OUTDOORS or with very good ventilation. Avoid breathing fumes.
