Consumer products giant Unilever has pioneered the use of a new black pigment for high density polyethelyne bottles which will make them detectable by recycling plant scanners and sorting machinery.
Set to be used first by leading brands Tresemmé and Lynx, the new pigment will make it possible to potentially sort and recycle an extra 2,500 metric tons of plastic bottles, Unilever said in a May 20 news release.
This is an equivalent of 1,250 family-sized cars, according to the consumer goods company.
In addition to launching the bottles in 2019, Unilever said it also aimed to introduce a minimum of 30 percent recycled content into TRESemmé and Lynx packaging this year.
Standard black plastic bottles, reinforced with carbon black pigments, are currently very difficult to detect by sorting machines in recycling plants as they absorb the near infra-red (NIR) light used for sorting.
Unilever did not elaborate on the details of the new pigmentation process, but said it involved "minor adjustments at the recycling materials facilities."
"We will be pleased to share our work and the insights generated with other manufacturers to enable wide use of this technology and approach," the company added.
The new solution was developed in partnership with United Kingdom-based plastic recycling charity Recoup and waste management partners Veolia, SUEZ, Viridor and Tomra.
Extensive trials, Unilever said, "have proven that this new pigment can be technically detected within those companies' material recycling facilities in the U.K."
The black polyethylene plastic packaging is "easily detectable with standard NIR units used around the world," according to Jürgen Priesters, vice president and head of business development at Tomra Sorting Recycling,
The material, he added, was "successfully tested several times and approved" in the Tomra Sorting GmbH test facility in the U.K.
Also commenting on the process, Richard Kirkman, chief technology and innovation officer, Veolia U.K. & Ireland, said his company used an innovative software solution and invest in sorting technology at its flagship recycling facility in Southwark, England, as part of the project.
"This, together with Unilever modifying the pigment in the black dye for their HDPE packaging, enables it to be successfully detected," he said, adding "if all recyclers and manufacturers follow this means black plastic becomes detectable black."
