Flame retardants for wool

Another flame-retardant treatment for wool based on exhanstion of an anionic species is the use of tetrabromophthalic anhydride, TBPA (Fig. 8.16), which hydrolyses to the carboxylic form during application. Use of TBPA at 10 % on weight of fabric under acid conditions provides effective flame retardancy that is dnrable to dry cleaning and mild laundering conditions (cold water washing at nentral pH). But TBPA is suspected to generate polybrominated dioxins under burning conditions. 

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Benisek L, Craven PC. Evaluation of metal complexes and tetrabromophthalic acid as flame retardants for wool. Textil Res J 1983 53 438-42. 

Potassium Hexafluorozirconate [16923-95-8]. This water-soluble com-poimd is a flame retardant for wool by the Zirpro process. Applied in combination with formic acid and citric acid, the fluorozirconate exhausts onto wool and after mild heating, provides a fairly wash-dimable flame-retardant finish. Wool upholstery for aircraft makes use of this treatment (19). 

Dibasic ammonium phosphate is used as a fertilizer as a fire extinguisher a flame retardant for plywood, papers, and fabrics to prevent afterglow in matches in purifying sugar as a flux for soldering tin, copper, zinc and brass and to control precipitation of alkah-soluble or acid-insoluble coUoidal dyes on wool. 

Wool Wool, though not as flammable as cotton, still needs flame retardation for specific applications, e.g., carpets, upholstered furniture in transport, etc. Ammonium phosphates and polyphosphate, boric acid-borax, and ammonium bromide can be successfully used in nondurable FR finishes for wool. Various commercial products have been reviewed by Horrocks.3 The most successful durable treatment for wool is Zirpro, developed by Benisek, which involves exhaustion of negatively charged complexes of zirconium or titanium onto positively charged wool fibers under acidic conditions at 60°C. The treatment can be applied to wool at any processing stage from loose fiber to fabric using exhaustion techniques. 

A stannic chloride pentahydrate—ammonium bifluoride formulation for fireproofing wool is commercially available and used in New Zealand and Australia (20) (see Flame retardants for textiles). 

Pyrosan. [Reilly-Whiteman] Flame retardant for polyester, wool, blends. 

Phosphonium salts are used as a source of ylids for alkene synthesis. Other applications include insecticides and fungicides [11]. Important applications of THPC are as flame retardants for textiles and paper, the improvement in uptake of colour and shrinkage resistance of wool, and the production of organic polymers by condensation with phenols or amines. Phosphonium salts also find... 

Flame-Retardant Treatments For Wool. Although wool is regarded as a naturally flame-resistant fiber, for certain appHcations, such as use in aircraft, it is necessary to meet more stringent requirements. The Zirpro process, developed for this purpose (122,123), is based on the exhaustion of negatively charged zirconium and titanium complexes on wool fiber under acidic conditions. Specific agents used for this purpose are potassium hexafluoro zirconate [16923-95-8] [16923-95-8] K ZrF, and potassium hexafluoro titanate [16919-27-0], K TiF. Various modifications of this process have been... 

High purity hexafluorozirconic acid and its salts are produced by Advance Research Chemicals of the United States, and Akita and Moritta of Japan. The technical-grade green-colored material is suppHed by Cabot Corp. of the United States. In 1993, the U.S. market for fluorozirconic acid was about 250,000 kg/yr the world market was less than 500,000 kg/yr. A principal part of this production is consumed by the wool, garment, and upholstery industries. The 1993 price varied between 2.4 to 6.6/kg depending on the quaUty and quantity required. Potassium fluorozirconate [16923-95-8], K ZrF, is commercially important the world market is about 750,000 kg/yr. The most important appHcation is as a fire-retardant material in the wool (qv) industry, for the manufacture of garments, upholstery for aeroplane industry, and children s clothes (see Flame retardants). The 1993 unit price was between 5.0 and 6.6/kg. 

These can be inorganic materials such as calcium silicate, mineral wool, diatomaceous earth or perlite and mineral wool. If provided as an assembly they are fitted with steel panels or jackets. These are woven noncombustible or flame retardant materials the provide insulation properties to fire barrier for the blockage of heat transfer. 

Ozone is being investigated for shrinkage prevention (182). Wool and blends of wool, cotton, and polyester have been finished to provide improved flame-retardant, durable-press, and shrinkage properties (183,184). Fabrics of these types are often used for uniforms or protective clothing (185). 

Flame relardanls are used in smolder-resistant upholstery fabric, combination flame retardant-durable press performance, flame-retardant treatments for wool, thermoplastic fibers (Tris. decabromodiphenyl oxide-polyacrylate finishes. Antihlu/e 19. nylon finishes), polyester-cotton fiber blends (THPOH-ummonju-Tris finish, decabromodiphenyl oxide-polyacrylate finish. THPC-amide-polytv illy I bromide) finish, THPOH-NHi and Fyrol 76. LRC-UX) finish, phusphonium salt-urea precondcn-satej. cotton-wool blends, and core-yam fabric,... 

Cotton, viscose, nylon, polypropylene, acrylic, polyester, or wool are generally used in carpets as the face or pile fabric over Neoprene latex. Carpets are usually flame retarded by back-coating with antimony-halogen system. The primary U.K. tests for carpet are BS 6307 198237 and BS 4790 1987,38... 

Even an antagonistic behaviour is reported for wooFpolyester blends. Both Zirpro finished wool and Trevira CS, which is inherently flame retardant modified... 

A semi-durable flame retardant application especially suited for wool, wool/nylon, wool/polyester blends. Laundering will remove this finish. 

Use Manufacture of carbon tetrachloride, trichloroethylene, chlorinated hydrocarbons, polychloro-prene (neoprene), polyvinyl chloride, hydrogen chloride, ethylene dichloride, hypochlorous acid, metallic chlorides, chloracetic acid, chlorobenzene, chlorinated lime water purification, shrinkproofing wool, flame-retardant compounds, special batteries (with lithium or zinc) processing of meat, fish, vegetables, and fruit. For information, refer to the Chlorine Institute, 2001 L St., NW, Suite 506, Washington DC 20036. 

Wool has been regarded as a relatively safe fiber from the flammability point of view. However, it could be flame retarded to a higher degree if required. Hendrix et al. (26) suggested a large improvement in fire resistance of wool by treatment with 15% H PO. Beck et al. (27) showed that weak acidic materials, such as boric acid and dihydrogen phosphate, are effective additives for flame retarding wool by the condensed-phase mechanism (increased char residue). 

Tetrabromophthalic anhydride. Flame retardant in production of unsaturated polyester resins and rigid PU polyols co-hardener for epoxy resins cost efficient additive for latex emulsions derivatives used as flame retardants in diverse applications (wire coating, and wool, etc.). Crystals mp = 279-281 insoluble in H2O. Ethyl Corp. Great Lakes Firm Chem. 

Flame retardant finish for technical wool fabrics. Within the technical textile sector, wool textiles requiring high levels of heat and flame resistance are limited in the main to the contract and transport furnishing fabric and protective clothing markets. The non-thermoplastic and char-forming characteristics of wool, coupled with an inherently quite high level of low flanunabiUty, make it an ideal fibre when handle, comfort, and aesthetics are also required. 

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