Clariant Helps Brands Go Green with Sustainable Colors, Additives for Plastics


CHARLOTTE, N.C.—As brand owners and packaging producers strive to reach sustainability goals profitably, Clariant made it a priority to develop solutions involving recycled, renewable and biodegradable materials, as well as technologies to help reduce material use and energy consumption through its Masterbatches.

“Major consumer brand companies are aggressively seeking ways to improve the environmental profile of plastics packaging, especially if they can do so while maintaining profitability," observed Alessandra Funcia, global head of segment packaging for Clariant. "We try to work with our customers and show them several different ways to realize their objectives and we always provide a complete business case analysis for the total package, including materials, manufacturing efficiency, productivity, etc."

Foaming Cuts Polymer Use, Saves Energy, Preserves Appearance

In conventional materials or in biopolymers, foaming has the potential to yield many environmental benefits, including reducing overall resin usage and weight—in some cases by up to 30 percent—often with no loss of physical properties, mechanical performance or appearance, even in challenging applications. For instance, when black, navy and other darker colors are used in injection-molded polypropylene, HYDROCEROL® chemical foaming agents plus Clariant-optimized molding conditions make it possible to achieve a smooth, glossy surface finish. This is an important improvement over the matte finishes and frosted looks that compromised critical appearance parts.

Material savings is not the only benefit. Lighter weight packaging is easier to transport so shipping costs and fuel consumption can be reduced.

In processing, HYDROCEROL reduces the melt viscosity of the base resin, allowing for faster extrusion rates and reduced cooling time, both of which contribute to shorter cycle times and, ultimately, lower energy costs and higher productivity.

Liquid or Solid

Most of Clariant's products can be supplied in traditional solid masterbatch form or using new liquid vehicle technology (LVT), which can offer significant sustainability and economic advantages in many applications. Liquid masterbatches disperse readily through the polymer matrix so, in some colors, the amount of colorant needed to achieve the desired look can be cut by 50 percent or more. This is especially true for translucent or transparent colors in clear polymers like PET, polyethylene and polypropylene. Liquids can be metered very precisely, eliminating the risk to over-saturating the color. When it comes time to change from one liquid color to another or from liquid color to solid, the switch can be made in a fraction of the time it takes to purge solid color from the processing machine so less scrap is generated. Liquid masterbatches can also be formulated so that they actually improve the flow of the polymer, resulting in faster fill times and shorter injection molding cycles, as well as improved extrusion throughput or lower required screw speeds.

Options for Biopolymers

As interest in biopolymers—plastics like polylactic acid (PLA) made from corn, sugar, starch and other natural raw materials—continues to grow, Clariant has been developing color and additive products for these renewable materials. RENOL®-natur masterbatches combine all-natural colorants with biopolymer carrier systems to provide a completely renewable and biodegradable solution.

More recently, Clariant introduced another option for biopolymer products and packaging, which offers a broader choice of colors and additive functionality. New RENOL-compostable and CESA-compostable masterbatches meet recognized U.S. and European standards for compostability and ecotoxicity, including the harmonized EN 13432:2000 standard. Yet, because they incorporate conventional (non-natural) additives and pigments, the new masterbatches may be more economical and process- and light-stable in some packaging applications.

Using More Recycled Plastics

Making it easier for customers to use more post-consumer recycled (PCR) material, Clariant has developed masterbatches specially formulated to work with the slightly off-color PCR resins available. Recycled polyolefin plastic, for instance, normally has a grayish cast that can mute the overall impact of color in these materials. Using ENIGMA® color and effects technology, designers can create packaging that not only has a better environmental profile, but also is attractive enough to compete for the consumer’s attention on store shelves.

 PET is one of the most commonly recycled materials but it is also highly vulnerable to thermal, oxidative and hydrolytic degradation, which results in loss of molecular weight and deterioration of processing properties. Clariant’s CESA-extend additive masterbatches, however, can repair polymer chains that have broken due to degradation, allowing the recycled material to be used in higher-value applications including sheet and bottles.

CESA-extend is also being used in PLA biopolymer film and foamed sheet to reduce material consumption, create a lighter weight end product, and improve performance properties. Even in its virgin state, PLA is inherently low in melt strength. As it does in recycled PET, CESA-extend can improve the melt strength of PLA during extrusion, resulting in a larger more stable film bubble even at higher line speeds. The additive masterbatch also has been found to allow development of smaller and more resilient foam cells when used in the production of foamed PLA sheet.

“It is important to remember that none of this technology is important if it cannot be used in a way that yields a product that the market will accept and purchase," Funcia said. "We are eager to partner with brand owners and major packaging converters in new application research any so that, together, we can make sustainability not only responsible but also profitable."