Bricks without straw?
Though remanufacturing with discarded PET bottles is highly efficient, material made from discards cannot, after all, get a grade of 100% in terms of quality. Almost inevitably there are other plastics mixed in, mainly polyethelene (PE, such as bottle caps) but sometimes even polypropylene (PP, like storage boxes) or polycarbonate (PC, as in baby feeding bottles).
Eddie H. Lin, the manager of the Filament Division in the Fiber Business Operations Center at Far Eastern New Century Corporation, the leader in manmade fibers in Taiwan, explains that when impurities get into PET pellets, the threads made from the adulterated materials break more easily. They are therefore suitable only for the manufacture of "spun thread," as inferior thread made by winding shorter threads together is known. This in turn is only used for less economically productive goods like quilt batting, carpets, non-woven cloth, or industrial-use fabrics.
"If you want to manufacture 'filament thread' that can be used to make cloth material of high economic value, you have to separate garbage very precisely right from the very start, and the bottles have to be sufficiently clean. But this is the most difficult part of the process to control," he advises.
Precisely because PET bottles, from the moment they are thrown into the recycling bin up to the moment they are made into thread, must pass through many hands and many steps, it is extremely difficult to meet the criteria just set out by Eddie Lin. This is why in most countries they limit themselves to remanufacturing only spun thread. For example, in China, which has the highest PET recycling volume in the world with 4.5 million tons of baoteping annually, more than 80% is suited only to making the lower-valued spun fibers.
With countries around the world caught in an eco-yarn quality bottleneck, how is it possible that, four years ago, firms in Taiwan began using recycled PET bottles to make the more challenging filament thread? Is there some secret that nobody else knows about?
"The answer is actually quite simple," says Fanny Liao. "We have been able to help downstream firms do the technological upgrading because we can rely on precise and thorough trash separation." Liao notes that after 20 years of information campaigns, Taiwan has gotten quite good at sorting out trash. When bottles of sufficient purity and cleanliness are available, the recycler's client firms only need to install machinery that can do a further step of sophisticated screening for impurities, and they can then manufacture filament thread that is virtually indistinguishable from that made directly from virgin raw materials.
Eco-friendly material made using the "3D weave" developed by Far Eastern New Century gives a three-dimensional feel where it touches the athlete's body. Because this weave allows air to flow in and sweat to evaporate out, the sportswear doesn't stick to the skin.