Wool is the original carpet fibre, the oldest in use. A natural fibre, it has many desirable characteristics. It offers good serviceability and beauty, takes dye well and has good resiliency. It is warm, soft and comfortable. Wool is highest in price of all fibres, and is only available in limited styles. It is also not as durable as most synthetics. However, many of the more economical man-made fibres can equal wool in most respects.
Polyamide or Nylon
Nylon is the strongest of all man-made fibres and carpeting of nylon is economical to produce. It offers excellent abrasion resistance and good crush resistance. It dyes well, is easy to clean and is available in a wide variety of styles and textures. "Natura Lustre" type yarns combine the appearance of wool with the advantages of nylon. All in all, nylon makes an outstanding carpet fibre ... so good that over 80% of carpet produced today is made with nylon. Quality for quality, a nylon carpet will outlive any other carpet you can buy.
Not all nylons are alike, however. The development of carpet nylon is expressed in terms of generations. The First generation of nylon was designed to "hide" dirt by reducing the transparency of the fibre. In the Second generation of nylon, the shape of the fibre was altered, which better reflected light, increasing its soil hiding appearance while enhancing its strength and resiliency. The introduction of specially designed filaments into the fibre in the Third generation nylons-virtually eliminated the problem of shocks from static electricity build-up. And finally, after 10 years of development and testing, Allied Corporation introduced Anso IV, the first Fourth generation nylon, which has soil and stain resistance built into the fibre itself, in addition to having the static shock resistance and other advantages of the Third generation nylon.
Often compared to wool, acrylics are light and bulky and feel more like wool than any other fibre. They offer fair abrasion resistance and good crush resistance. Carpet of acrylic is more expensive to produce than nylon. Acrylics are usually found in velvet and level-loop constructions. The use of acrylic in carpeting has declined over the years.
Polyester feels somewhat like wool and offers good abrasion resistance and bulk. It has fair to good crush resistance and is less static-prone than other man-made fibres, but is more susceptible to oil-based stains and soil.
Olefin or Polypropylene
Olefin is used primarily in applications where its resistance to fading and staining is most important. It offers good abrasion resistance and strength, but poor resiliency. In production, olefin approaches nylon in economy.
What about Soil-Resistant Treatments?
Many residential carpets are produced with special surface treatments. These topical treatments are sprayed onto the carpet, and act as a shield, helping the carpet stay clean. But with cleaning and use, the treatments can wear away. The soil and stain resistance of the new Fourth generation nylons, however, is built right into the fibre, so its protection is always there.