The History of Fire-Retardant Fabrics
- Melting temperature is just one factor to be considered.temperature image by berkay from Fotolia.com
To be considered flame retardant, a fabric must not ignite or create self-sustaining flame when subjected to a heat source. Most flame-retardant compounds share common elements such as boron, phosphorus, nitrogen and halogen. Transition temperature, melting temperature, pyrolysis temperature, combustion temperature and the limiting oxygen index (LOI) must all be taken into consideration when determining the flame-retardant factor of fibers. Transition temperature is the temperature at which material changes from one crystal state to another. Melting temperature is the temperature at which a solid becomes a liquid at standard atmospheric pressure. Pyrolysis is the chemical decomposition of condensed substances by heating that occurs spontaneously at high enough temperatures. Combustion or burning is the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species. The limiting oxygen index is the minimum concentration of oxygen, expressed as a percentage, that will support combustion of a polymer. Most flame-retardant compounds share common elements such as boron, phosphorus, nitrogen and halogen. - Vinegar is the earliest recorded flame-retardant substance.botella image by federico igea from Fotolia.com
The history of fire-retardant products begins in 360 B.C. when timbers were coated with vinegar to protect against fire. In 83 B.C., wooden siege towers were protected from the fire of the Romans with alum, which is a white crystalline double sulfate of aluminum.
Pliny the Elder described an asbestos tablecloth in 77 A.D. that could be cleaned easily by heating until red hot. He later revealed that workers exposed to asbestos often experienced serious health problems. - In 1782, the Montgolfier brothers discovered that heated air from a fire directed into a paper bag made the bag rise.Hot air balloon image by MAXFX from Fotolia.com
Nicholas Sabbatini, in 1638, recommended a clay and gypsum combination be applied to painted canvas theater props to protect against fire after a series of fires ravaged local theaters.
Obadiah Wyld received the first patent in Great Britain for developing a flame-retardant mixture of alum, ferrous sulfate,and borax in 1735.
The Montgolfier brothers, born in Annonay, France, were inventors of the first practical hot-air balloon. Joseph-Michael and Jacques-Ètienne applied alum alone in 1798 as a flame-retardant coating on their balloon. - Gay-Lussac made recommendations for applying flame retardants to theater props.theater image by Ingrid Walter from Fotolia.com
In 1820, French chemist Gay-Lussac, after being commissioned nearly 40 years prior, recommended using mixtures of ammonium phosphate, ammonium chloride and borax to reduce the flammability of textiles used in French theaters. This combination proved highly effective and is often used today. - A firefighter's gear is designed to be flame retardant and able to withstand high temperatures.feu de savane image by Philippe SURMELY from Fotolia.com
By the mid-19th century, numerous flame retardants had been tested for textiles. The combination found most effective was ammonium phosphate, ammonium sulfate and a mixture of ammonium phosphate with chloride. At the beginning of the 20th century, William Henry Perkin became the first person to systematically study the mechanisms of flame retardancy. Modern flame retardants for textiles, papers and fabrics are based on his fundamental research, including the 1953 discovery of Tetra(hydroxymethyl)phosphonium chloride (THPC). THPC is a light yellow, clear liquid applied as a flame retardant to cotton and Dacron-cotton fibers, plastic, paper, painting, coating, furniture and building materials. Over time, THPC has been altered and improved upon, creating alternative fire-retarding mixtures. Research continues to improve flame-retardant cotton and blended fabrics used by the U.S. military, NASA and numerous fire departments. Flame retardants applied to all types of textiles have undoubtedly saved lives and property.
