Natural fibers used with carpet are produced either by insects, animals, or even plants. The fibers that are produced by insects or animals are known as protein fibers. Those that are made by plants are known as vegetable fibers. Vegetable and protein fibers share the common disadvantage that they are both very absorbent and will have extended drying times when wet cleaned – which can lead to mildew, shrinkage, and even dry rot.
Wool fiber is produced from the fleece of lambs or sheep. Wool of carpet is imported from countries such as England, Australia, and New Zealand. Wool is the oldest and considered to be the finest of all carpet material.
The ability of wool to stretch up to 40% of its original length and the fact that it can be bent back and forth more than 180,000 times without breaking makes it very resilient. Wool is the most expensive material for carpet, although it is also the best you can buy.
The fiber of silk is produced by the larva of various insects known as silk worms. The silk, in continuous lengths from 300 to 1600 yards is spun to produce the cocoons. As a fiber, silk is naturally non flammable, strong, and not affected by static charge problems – even at low humidity.
This type of fiber is produced by plants and normally not used as face yarns. These types will however, show up as backing materials of tufted as as well as carpets that have been woven.
Cotton is a vegetable seed fiber that is produced from the cotton plant. The primary use for this fiber is yarns woven in carpet or rugs. Cotton is resistant to alkaline solutions and becomes stronger when it is wet.
The biggest disadvantages to cotton is the fact that is the most absorbent of all fibers and requires extended drying times after being wet cleaned. It is also easily damaged by acids, stains easily, mats down, soils quickly, and is subject to mildew, dry rot, and shrinkage.
The fiber of jute is produced by the jute plant which grows in South America, Pakistan, and even in India. The stalk of the jute plant is where the longer coarse fibers are obtained, located between the outer bark and within the inner pulp.
Jute is normally used as weft yarns, across the width, in woven carpets and as a backing material in the construction of tufted carpets. Jute is an inexpensive material that also serves other uses than just carpet. Like all other fibers, this one has disadvantages as well. The fiber is weak when it becomes wet and is also subject to dry rot, shrinkage, and mildew.
The fiber of sisal is produced by the leaves of the agave plant. Sisal is very strong and primarily used for making rugs, sacking, rope, and even carpet. The fiber stains easily and is also very difficult to clean. Wet cleaning can also cause shrinkage so its best to use low moisture methods.
There is quite a bit of confusion about rayon and it is easy to understand why. Rayon is a synthetic fiber that is produced from natural cellulosic fibers of wood pulp or cotton. The material is put through several chemical treatments which help to turn it into a synthetic fiber.
Primarily, rayon is used for area rugs because of its silk like appearance. It can be damaged by acids, has low resistance to abrasion and is also prone to cellulose browning.