Clariant continues to develop new technologies to improve the recyclability of plastics and provide packaging and product developers with more color options. Recent developments include darker and darker colors that require the use of carbon black pigments, as well as the inability of near-infrared (NIR) sensors used in automated polymer sorting systems at recycling centers to detect carbon black pigments. But with new color concepts developed at Clariant's Colororworks design and technology center near Milan, Italy, it is now possible to explore darker, more mysterious color spaces without using carbon black. 

The development of polyester (PET), high-density polyethylene (HDPE) and polypropylene (PP) in both virgin and post-consumer recycled (PCR) form is ongoing. In most automated sorting systems, infrared light strikes the plastic material and the system can sort a variety of materials because different polymers reflect the light in different ways. Unfortunately, the carbon black pigments typically used to make black and other deep blacks absorb all or most of the near-infrared light, so the sensors can't "see" the black packages, let alone separate them. Late last year, Clariant launched CESA IR, a range of masterbatches that make black plastics visible in the near infrared. 

The effect has been tested by TOMRA Sorting Recycling in Norway. But Clariant Colorork Robertoooo Romanin designers wanted more options than just black. Some of the unique luxury facials, nourishing serums and essential oils are packaged in dark colors. However, most still use charcoal black and therefore have recyclability issues. To address this issue, the ColorWorks team started a project to develop colors that darken without the use of carbon black using CESA-IR technology. Initially, three colors were created:-Dark Brown, Dark Velvet Green, and Noble Dark Blue. 

All three colors are saturated, almost black, but allow the colors to shine, evoking elegance, uniqueness, tradition and boldness. Groeseling, Clariant's Circular Economy and Sustainability Manager for Europe, Middle East and Africa "Until now, manufacturing dark-colored plastics that can be detected by near-infrared spectroscopy has required careful control of the amount of carbon black used, which has not always been feasible in the real world."" Situation. So we've been looking for-and found it-new solutions that are so dark that we can eliminate carbon black completely from these new detectable formulations. "The range is suitable for all major packaging polymers including PET, polyethylene and polypropylene (including post-consumer recycled resins) in all different packaging applications including trays, bottles and caps.