For the last 40 years the growth of the nonwovens industry has been driven by the ready availability of synthetic fibres cheaply made by exploitation of non-renewable fossil reserves. Disposable nonwovens, from coverstock to core-wrap, and durables from geotextiles to home furnishings, have evolved to use polypropylene, a low-cost by-product of petroleum refining, which has become the fibre for nonwovens.
The high-volume converted products which use the disposable nonwovens – diapers especially – have grown even faster due to performance improvements obtained by replacing woodpulp with superabsorbents based on the same non-renewables. The life-enhancing convenience of disposable diapers allowed consumers to forget that their disposal via the solid waste stream diverted human excrement from its traditional treatment in the sewage systems, and made regular collection of rubbish an aesthetic and public health necessity.
Here’s a chronology:
- 1960’s: P&G developed the one-piece Pampers diaper – kitefold – using the same materials but with an integrated plastic back, which meant it had to be disposed of in the solid waste stream. Consumer concerns about human faeces being spread on landfill, were soon overcome. Sales of rayon, then the cheapest fibre for coverstock, soared.
- 1970’s: Rayon became more expensive than polyester so polyester was blended with rayon to make coverstock. “Surface dryness”was discovered with the less wettable synthetics.
- 1980’s: Polypropylene staple, thermal bonded, becomes cheaper than rayon/polyester blends and hence becomes the coverstock of choice. Synthetic superabsorbents are blended with woodpulp to reduce leakage and improve surface dryness further.
- 1990’s: Superabsorbent and elastic content increased, more 100% PP coverstock used per diaper as cuffs and textile-like backsheets are added. Children staying in diapers for longer. Training pants developed for older children.
- 2000’s: 100% PP Coverstock switches to spunbond from staple, thanks to amazing improvements in the formation of lightweight achieved by Reicofil and others. Even core wrap is switching to PP from cellulose tissue. Diaper use growing in the world’s most populus regions (
China, ) India