Swiss chemicals giant Clariant has introduced a new range of black pigments for plastics, allowing them to be detected by near-infrared (NIR) wate sorting systems.
The new Solvaperm Black PCR, Graphtol Black CLN and Polysynthren Black H products will be introduced at K 2019, which is taking place 16-23 October at Messe Dusseldorf.
Black plastics, particularly food trays, have been difficult to recycle due to them not being readily identifiable in NIR sorting systems.
This generally means they go directly to landfill.
The new products are a direct alternative for carbon black pigments which absorb the NIR light.
The black colourants preserve the NIR identifiability of common packaging plastics such as HDPE, LDPE, PP, PET, PS, PA and PVC. Also, these include thermoplastics used in consumer electronic equipment.
Sorting accuracy of products using the black colourants was verified with a hand-held analyser device using a technology comparable to that of NIR automated sorting systems.
Clariant notes that the new products will allow packaging producers to choose black plastics, which are favoured due to their neutral background, which highlights products.
The company further adds that the products could support dedicated recycling streams for black plastics.