Prerequisite for the sustainable use of non-renewable resources and the reduction of plastics waste polluting our environment is the creation of a circular economy based on comprehensive closed-loop recycling of plastics. There are several criteria that must be fulfilled in order for closed-loop recycling to make ecological and economic sense.

To ensure optimal recyclability plastic containers need to be transparent or light-coloured. Dark and opaque colours interfere with the optical sorting process. If design and/or colour do not allow a plastic container to be positively identified by sorting machines, the container will go to the waste stream and not be recycled.

For high-density Polyethylene bottles, Polyethylene or Polypropylene closures are best.