How a carpet performs after it has been installed depends upon many things … carpet construction, yarn system, the type of installation, the quality of the maintenance and the type of fiber that has been used. Each of the fibers used to produce carpets has distinct characteristics and performance properties that do not change.
Nylon is the most important fiber used in the carpet industry today. Bulked continuous filament (BCF) and staple nylon represent approximately 63% of the carpet market. Nylon is the easiest fiber to dye and, as a result, the consumer has available an impressive choice of colors. In addition, this fiber is thermoplastic which means that it can be deeply heat-set, giving the carpet manufacturer the ability to produce cut-pile carpet such as saxonies and friezes that perform as well as loop-pile carpets.
Nylon is the fiber most resistance to abrasion. There is possibility that a nylon carpet will “ugly” out, if not properly maintained, but nylon will not wear out. Nylon is also a very resilient fiber, reducing matting and crushing in traffic areas. In the area of soiling and cleaning, nylon performs very well, but unless it is treated for stain removal with one of the stain-blocking products, this fiber can be permanently stained very easily by common household spills.
Nylon 6 and 6.6
There are two types of commonly used nylon carpet fiber that have slightly different properties. Nylon type 6.6 is the “harder” of the two fibers, making it more stain resistant. Type 6 is a softer, more porous nylon fiber allowing more rapid penetration of dye in the manufacturing process which enables a variety of colors and patterns to be easily applied. Because of these characteristics, type 6 nylon will accept staining agents more readily and show the effects of light fading and traffic soiling more quickly than type 6.6.
The use of polypropylene in the carpet industry has increased rapidly. This is primarily because of polypropylene's lower cost and the ease in which almost all common household stains can be removed from a polypropylene fiber. In the USA, polypropylene is only readily available in solution dyed form. This means that the carpet will resist color fading, but the consumer will not have the choice of colors that are available with nylon fibers
Polypropylene is not a thermoplastic fiber and its most undesirable characteristic is its lack of resilience, limiting the ability of saxony and frieze styles to remain heat-set as well as nylon. Although the carpet construction can be made so dense that crushing is resisted, once a polypropylene carpet becomes crushed, it stays crushed.
Polypropylene has an affinity for oil-based soils, creating the need for more aggressive cleaning procedures to restore the appearance of heavily soiled polypropylene carpet. Some solution dyed fibers do initially soil a little more rapidly than fibers that are dyed after they are tufted because of residual oils left in the tufted process.
Polyester is dyed at the carpet mill in a manner very similar to nylon. Like nylon, this fiber is a true thermoplastic fiber, and so it will perform well in heat-set carpet styles. Although not as resilient as nylon, polyester does perform better in this area than polypropylene. In the area of spot removal, polyester is better than a stainblocked nylon but not as good as polypropylene.
Wool fibers have performed in carpets over a longer period of history than any other fiber. Although wool does not have the resistance to abrasion that is available in the man-made fibers, it does have an excellent balance of all the other important properties. Resilience is excellent, soil hiding is excellent, and cleaning and stain removal characteristics are very good.
Polytrimethylene Terephthalate (PTT)
Preliminary tests show that PTT has characteristics that make it suitable for carpet. In addition to good resilience, PTT also has great stain resistance to common household spills without a stain-block treatment. The cleanability features of this fiber are very good. Expect to see this product on the market.