Base Layers Made From Recycled PET Bottles

Coldpruf Eco Base Layers

An environmental movement the Outdoor industry has long since embraced is reducing the amount of disposable plastic bottles in landfills. One effort, encouraged by the reusable water bottle manufacturers, is to eliminate disposable plastic bottles altogether. Another is to recycle what has already been manufactured. Along these lines, North Carolina-based Indera Mills, has created ColdPruf ECO, a range of base layers for colder climate adventures using waste PET bottles. These PET bottles are reproduced into performance polyester staple fibers and spun into thermal crews and leggings.

What many fail to realize is that about 60% of the global production of PET (polyethylene terephthalate) is actually used to make synthetic fibers for textiles in the first place, only 30% for bottles. So it’s a natural fit to reconvert waste PET bottles into apparel. Companies like Patagonia have doing just that in the Outdoor Industry for close to 20 years.

There are a number of benefits to recycling PET bottles, as well. First, of course, is the argument of reducing landfill given the hundreds of years it takes for plastics to biodegrade. Second is limiting the use of new resources, particularly given PET is derived from elements of both refined oil and either hydrocarbons or natural gas. And lastly, It takes less energy to reconvert a waste PET bottle back into the original polymer for use as polyester fibers than making virgin polyester. Savings estimates range from 1/3 to roughly 1/2 the energy.

Indera Mills has been knitting underwear garments for nearly 100 years, focusing solely on winter weight products more recently. The company is now one of the largest suppliers in the US of thermal underwear products, both under the Indera Mills and private label brands. The design, knitting, cutting and distribution of products such as ColdPruf ECO base layers are still done in the US, with sewing handled in Mexico.

Indera Mills uses a rating system called Thermachoice to help you select the right garment for various weather conditions and activities. These range from Cold to Extreme, and Low Activity to High. ColdPruf ECO base layers are geared for low activity, with different designs for either Colder weather or Extreme Cold.

The ColdPruf ECO Pro-Tek line is a 100% recycled performance polyester in a waffle weave and is treated with an antimicrobial odor-blocking technology. The Eco-Terra version blends recycled performance polyester with 30% merino wool fibers in a single layer Raschel Knit that traps air for added warmth. Shop around for the best prices. You should be able to find Eco-Terra items for under $30 and Eco Pro-Tek for less than $25.

– Don Jurries

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  1. I think base layers made from recycled PET are a really bad idea. Polyester is made with antimony as a catalyst; Bill McDonough and the cradle to cradle people write:

    “Along with being a carcinogen, antimony is toxic to the heart, lungs, liver and skin. Long-term inhalation of antimony trioxide, a by-product of polymer production, can cause chronic bronchitis and emphysema.”

    They will not certify products made from conventional recycled polyester because of concerns about the antimony leaching out, and they are talking about carpet and upholstery, not a base layer of clothing against your skin for days on end. There are companies making virgin polyester with other catalysts, but the recycled stuff will not be antimony free and if it can leach out of bottles (it does) it can leach out of your base layers. Between the sweat and the heat and the chafing, putting this stuff against your skin is nuts.

  2. I think base layers made from recycled PET are a really bad idea. Polyester is made with antimony as a catalyst; Bill McDonough and the cradle to cradle people write:

    “Along with being a carcinogen, antimony is toxic to the heart, lungs, liver and skin. Long-term inhalation of antimony trioxide, a by-product of polymer production, can cause chronic bronchitis and emphysema.”

    They will not certify products made from conventional recycled polyester because of concerns about the antimony leaching out, and they are talking about carpet and upholstery, not a base layer of clothing against your skin for days on end. There are companies making virgin polyester with other catalysts, but the recycled stuff will not be antimony free and if it can leach out of bottles (it does) it can leach out of your base layers. Between the sweat and the heat and the chafing, putting this stuff against your skin is nuts.

  3. I think base layers made from recycled PET are a really bad idea. Polyester is made with antimony as a catalyst; Bill McDonough and the cradle to cradle people write:

    “Along with being a carcinogen, antimony is toxic to the heart, lungs, liver and skin. Long-term inhalation of antimony trioxide, a by-product of polymer production, can cause chronic bronchitis and emphysema.”

    They will not certify products made from conventional recycled polyester because of concerns about the antimony leaching out, and they are talking about carpet and upholstery, not a base layer of clothing against your skin for days on end. There are companies making virgin polyester with other catalysts, but the recycled stuff will not be antimony free and if it can leach out of bottles (it does) it can leach out of your base layers. Between the sweat and the heat and the chafing, putting this stuff against your skin is nuts.

  4. Lloyd,

    Very astute point! Antimony is a known carcinogen, yet is an important catalyst used in making most polyester. This applies to virgin polyester, as well as recycled polyester. Regardless, polyester remains a dominant fiber, comprising about 65-70% of the world’s production of synthetics. To date, there simply isn’t a commercially viable alternative to replace Antimony for that much volume. Other metals like Titanium and Germanium have been tried as catalysts, but are still expensive options.

    What textile manufacturers will generally claim is that Antimony bonds with the polymer so tightly in the production of the polyester fiber that it won’t leach from clothing. Or if it does, it’s below the safe limits defined by many governments. Be aware that you are exposed to Antinomy in very, very minute quantities every day, potentially in the air, food and water – as it’s a naturally occurring element – periodic table, atomic number 51. And Antimony and it’s various compounds like Antimony trioxide appear in a lot of other products, particularly as a flame retardant, possibly including the mattress on your bed, in glass, ceramics, and in the vulcanization process of rubber.

    Where Antinomy really becomes environmentally problematic is with exposure to high temperatures, which occurs during the dying process for virgin polyester, for example, or in the recycling process of waste PET bottles. Antimony trioxide gets released into the air and wastewater, which, if not contained or treated, has the potential to harm living systems.

    I’m hoping Antimony goes the way of BPA when someone comes up with a commercially viable alternative. Until then, you’ll have to make a personal choice, which will apply to polyester in general, and a lot of other products, as well.

    Thanks again for your comment. It’s very much appreciated.

    Regards,

    Don Jurries

  5. Thanks for your response. I think I should temper my comment above by agreeing with you, particularly about your BPA analogy. It was easy for people to choose to change their polycarbonate bottles because there were technical alternatives; for the epoxy lining of cans, there still are not any, so you have to make a much more difficult choice.

    “Nuts” is perhaps an overstatement.

  6. Thanks for your response. I think I should temper my comment above by agreeing with you, particularly about your BPA analogy. It was easy for people to choose to change their polycarbonate bottles because there were technical alternatives; for the epoxy lining of cans, there still are not any, so you have to make a much more difficult choice.

    “Nuts” is perhaps an overstatement.

  7. Thanks for your response. I think I should temper my comment above by agreeing with you, particularly about your BPA analogy. It was easy for people to choose to change their polycarbonate bottles because there were technical alternatives; for the epoxy lining of cans, there still are not any, so you have to make a much more difficult choice.

    “Nuts” is perhaps an overstatement.

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