Griffin Dyeworks & Fiber Arts

Understanding Mordants and Modifiers

Caustic Soda


Description: Alkali modifier, off-white deliquescent hygroscopic pellets or flakes, 13-14 pH in 5% solution; in essence a solid form of chlorine bleach.
Other Names: Sodium hydroxide, caustic salt, fotofoil etchant, lye, red devil lye, soda, soda ley, soda lye, sodium hydrate, white caustic
Dye Use: Bleaches, develops and oxidizes indigo, neutralizes acids after urine went out of style (for some strange reason!). Works much like lye (potassium hydroxide) and is just as dangerous.
Best On: Cellulose fibers
Dye Recipe: 2 tbsp to 1 lb fiber to remove color. See indigo vat recipe for other use.
Safety: Chemical hazard! Very corrosive when wet; causes severe burns on contact, can permanently blind if splashed into eyes! Inhalation can result in burns to entire respiratory system
Disposal: Neutralize with acid, dilute and pour down toilet
Alternative: Soda ash, lye, potash
Source: Chemical supply house

CODES: c = cup; gal = gallon; lb = pound (weight); tbsp = Tablespoon; tsp = teaspoon / [AF] Anglo-French; [Ar] Arabic; [AS] Anglo-Saxon; [Dan] Danish; [Du] Dutch; [Fr] French; [Ger] German; [Gk] Greek; [It] Italian; [L] Classical Latin; [LL] Late Latin; [ME] Middle English; [ML] Modern Latin; [OE] Old English; [OF] Old French; [ON] Old Norse; [OS] Old Saxon; [Port] Portuguese; [Sp] Spanish; [Sw] Swedish / CE = Common Era; BCE = Before Common Era

left arrow Back to Understanding Mordants and Modifiers | left arrow Previous: Bran | Next: Chalk right arrow