Urea

UREA: CH₄N₂O

Description: Alkali modifier of synthetic nitrogen; colorless to white pellets or powder, slight ammonia odor; excreted in human and animal urine, precipitated around 1173, first chemical in 1799, synthesized in 1828.
Other Names: Carbamide, carbamide acid, carbonyldiamide, carbamide resin, isoruea, prespersion, pseudourea, U-15, ureaphil, ureophil, urevert, varioform, [L] urina
Dye Use: Dye solvent, cotton mordant, indigo vat reducing agent, good with weld, synthetic dye color stripper, keeps moisture in fiber long enough for dyes to bond. Longer shelf life and 6 times stronger, than Sodium Hydrosulfite.
Best On: Cotton, linen
Dye Recipe: To strip out additives or to mordant cotton, mix 1-1 1/4 tbsp urea, 1 1/4 tbsp washing soda, 3/4 c vinegar. Bring to gentle simmer for 20 min, then soak wool 1 hour, wash with soap to rinse well. Add 1/2 c white vinegar to last rinse. Can also be used as an after-rinse by steeping dyed goods 5 minutes. Too much heat can damage fiber.
Safety: Mild skin and eye irritation, can give off irritating and potentially toxic ammonia-nitrogen dioxide fumes if heated too high. Wear a mask when handling this chemical.
Disposal: Dilute and pour down toilet
Alternative: Ammonia, urine
Source: Griffin Dyeworks

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

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