Flame retardants for Wool

Wool fibres are inherently less flammable than most other fibres; however, some fire-retardant treatment is usually necessary in order to meet specific flammability tests. One well known process is based on hexafloro zirconate and titanate salts. These products can be applied by exhaustion and pad process under acid conditions (at pH<3).The heavy metal complex anions from ionic and other polar bonds with the wool fibre, similar to dyestuff anions. The fireretardancy mechanism is thought to take place in the condensed phase through zirconium ions or zirconium compounds that enhance or catalyse the char formation. The hexafluoro titanium salt is more effective and cheaper, but yellow shade is imparted to the treated wool, which is increased by exposure to light. The finish is durable to dry cleaning and water washing up to 40