Consumer goods giant Unilever has developed new black pigment for its High Density Polyethelyne (HDPE) bottles, allowing hard-to-recycle containers to be detected and sorted by scanners at recycling plants.
Image: Unilever's TRESemmé brand. Photo: courtesy of Unilever UK.
The firm expects the new detectable black pigment to result in further 2,500 tonnes of plastic bottles to be potentially be sorted and sent for recycling annually.
The automatic optical sorting machines in recycling plants usually fails to detect standard black plastic bottles as the near infra-red light emitted by the machines is absorbed by the ‘carbon black’ pigment traditionally used to colour the products.
As a result of the process, the black plastic bottles are invisible to the sorter, making them rejected and sent for waste.
Following extensive trials in partnership with RECOUP and waste management partners Veolia, SUEZ, Viridor and Tomra, Unilever has validated that the new pigment can be technically detected within their material recycling facilities in the UK, with minor adjustments to scanners.
The new pigment is planned to be introduced across Unilever’s TRESemmé and Lynx brands, which will see a minimum of 30% recycled material included back into new packaging.
Unilever UKI general manager Sebastian Munden said: “We’ve been working on a solution for black plastic for some time, and this move to using detectable black plastic in our TRESemmé and Lynx bottles means we will potentially be removing around 2,500 tonnes of plastic from the waste stream.
“Unilever has committed to ensuring that, globally, all of our plastic packaging is fully reusable, recyclable or compostable by 2025, and to using more recycled plastic content in our packaging.”
The consumer goods firm said that the new detectable bottles, which will be phased in during 2019, will allow the firm to further ‘close the loop’ and include the recycled black plastic back in new packaging.
WRAP, which manages The UK Plastics Pact, strategic engagement manager Helen Bird said: “We now call for wide scale adoption of detectable black pigments by brands and retailers, and the sorting and reprocessing of that packaging by the recycling sector.”