Carpet Fibres

This document provides information about the various types of carpet flooring.

Wool vs. Synthetic Fibre

The value of wool is as long-lasting as the fiber itself. Inherently flame retardant, resistant to dirt and crushing, it is naturally superior to synthetics. See for yourself !

The Weaknesses of Nylon (polyamide) are:
  • Inferior handle (feel) compared to wool
  • High affinity for soiling
  • Poor resistance to burning (it melts)
  • fiber surface damage through use (leads to increased soiling, reduced oil release)
  • Damaged by acids (e.g., formic acid).
  • Susceptible to degradation by sunlight
The Drawbacks of Polypropylene are:
  • Organic solvents and oxidizing agents cause fiber to swell and lose strength)
  • Lower abrasion resistance than polyamide
  • Poor resilience
  • Low melting point
  • Susceptibility to soiling
  • Very poor dye-ability
  • Susceptible to oil-based stains
The Disadvantages of Polyester are:
  • Less resilient than wool or polyamide
  • Range of lustres limited
  • Sensitive to cigarette burns
  • Lower soil resistance/inferior soil release than wool
  • Poorer abrasion resistance than polyamide
  • Degraded by ammonia
The Weaknesses of Acrylic are:
  • Lower abrasion resilience than polyamide
  • High soiling propensity
  • Poorer resistance to burning (although flame retardant variants are available), but releases toxic gases (contains cyanide group).
  • Fuzzing and pilling in coarse gauge loop pile
  • Limited resistance to some organic solvents and strong alkali

Moth-resist Treated Wool Carpets

Separating Fact from Myth

Most wool and 80/20 carpets are treated with moth-resist agents. Why? Because even moths enjoy wool's natural goodness. Sounds silly, but it's true. If wall-to-wall wool carpets are not treated, infestations of moths in the home is possible -- and that can lead to damaged carpets, wool garments, upholstery, blankets, and more.

Moths and other wool-eating insects require dark, undisturbed places, which is why infestations in the home usually occur around skirting boards, or under large furniture. Regular traffic and normal carpet cleaning usually protect easily accessible areas of carpet. Less busy areas are vulnerable and benefit from the moth-resist agents.

Moth-resist Treated Wool Carpets and Human Health

Moth-resist treated wool is harmless to humans and pets. In fact, even wool-eating insects cannot be harmed by the mere contact with the treated fiber; they must eat and digest it before the agent takes effect.

Only small amounts of the agents, with extremely low toxicity, are applied by manufacturing processes. Complete penetration of the agent into the wool fibers ensures that the treatment is resistant to carpet cleaning. Wools of New Zealand manufacturing partners ensure that the correct amount of agent is applied - too much is unnecessary and wasteful, too little would not protect the carpet adequately.

And more good news is that new methods of industrial insect-resist treatment discharge little or no agent into the environment.

About the Moth-resist Agent Permethrin

The most widely used moth-resist agent is permethrin, a synthetic pyrethroid. Pyrethroids are chemically similar to pyrethrum, an insecticide occurring naturally in a number of chrysanthemum varieties. Permethrin is widely used in agriculture, for the domestic control of insects and as a wood preservative.

Scientific Study Dispels Myths

The most authoritative publication on the subject of the effects of permethrin on human health is the World Health organization's (WHO) Environmental Health Criteria 94 on permethrin, published in 1990. The following statements are taken directly from the WHO report:
  • No poisoning cases (involving permethrin) have been reported
  • There are no indications that permethrin has an adverse effect on human beings when used as recommended
  • The exposure of the general population to permethrin is expected to be low and is not likely to present a hazard provided it is used as recommended
  • The likelihood of permethrin causing malignant diseases such as cancer ("oncogenic effects") in human beings is extremely low or non-existent

When used in the manufacture of wool carpets, three factors ensure that the treated carpet is safe:
  • Very low toxicity of permethrin to humans and domestic animals
  • Penetration of the chemical into the wool fiber during manufacture
  • Low level of permethrin applied to wool