Process for flameproofing cellulosic fibers prior to dyeing

摘要

Cellulosic fabric is dyed by affixing a hydroxymethyl phosphonium-nitrogen based polymer to the fabric and thereafter dyeing it with a cotton dye having anionic groups, in an acidic or neutral environment. In addition, a new method of affixing the polymer to the fabric is provided comprising contacting the fabric with a solution of urea and a precondensate of urea and tetrakis hydroxymethyl phosphonium salt.