The synthetic down in puffy jackets comes at an environmental cost. One stage of the manufacturing process that creates the insulation involves giant ovens. And those big ovens need fuel. That fuel is typically either coal or liquid petroleum gas in textile factories in Asia. The amount of energy it takes to heat these ovens is enormous. The giant ovens are around 300 to 356 degrees Fahrenheit, and the polyester must make multiple trips through them, for a total cooking time of three to four minutes. The biggest culprit with regards to carbon dioxide emissions is the thermal-bonding oven.
The ovens serve a key purpose: they bond polyester fibers together to create the insulation. That part of the process involves four different types of recycled polyester, plus one more type of polyester (not from a recycled source) that melts at a lower temperature than the other fibers. It melts and it attaches itself to the other surrounding fibers. That’s what makes the insulation not fall apart once it’s in garment construction.
However, PrimaLoft that makes down jackets has devised a new method that doesn’t require ovens at all or the binding agent made of non-recycled polyester. Instead, air cures the polyester blend—it travels through the ambient air of the factory on a conveyor-belt-like apron.
