Advances in PET additives

Manufacturers are looking for savings in material costs while requiring flexibility and performance WITH an increasingly active lifestyle across the Middle East, on the go beverages in polyethylene terephthalate (PET) bottles is becoming the norm. According to Euromonitor International, PET is the most popular packaging material for beverages worldwide with consumption at 45 million tons and annual growth of 6%. Growth in the region is even stronger at 20% per annum. Amid this extraordinary growth, beverage makers are facing increasing challenges owing to the rise of packaging material prices and high cost of production. It's no surprise therefore that companies are increasingly looking for alternatives, whether it is considering the use of recycled PET preforms or lightweighting PET bottles. An essential part in the process of creating PET, whether from recycled or virgin resin, is the masterbatch. This includes pigments to colour the polymer and additives that add strength or improve barrier quality in the final bottle. Recent developments are discussed here. High quality ecological dyes PET has an inherent yellow tinge. Although this has no impact on the contents of the bottle in any way, this is of concern to beverage producers who desire to market their products in clear see-through containers. Potential customers tend to judge the quality of a product based on visual characteristics, so milk must be white, whereas mineral water is expected to be colourless. Safe dyes for PET must satisfy the high purity and safety regulations in place on a worldwide basis for food packaging and food contact applications, including approval from the United States Food and Drug Administration (FDA). "Macrolex" Red 5B, Violet 3R, and Blue 2B from the Functional Chemicals Business Unit of specialty chemicals company Lanxess can help to offset this fundamental issue. Leading PET manufacturers use these FDA-approved dyes during the polymerisation process to produce a crystal clear colourless or blue-tinged transparent PET. Fruit juices require protection from UVlight, and therefore PET bottles containing such liquids are colored either green or dark brown. PET color masterbatches may contain a combination of different Macrolex dyes to allow the manufacturers to optimise the PET color for the respective applications. A critical feature of Macrolex and one of importance to the PET manufacturers is that the dye does not migrate from the PET into the liquid. This inherently implies that the dye is safe for use in consumer products. These dyes are available in a variety of delivery forms, including microgranules. Being hollow spheres, the microgranules are easily crushed and dissolve rapidly and evenly in plastic. In addition their good flowability ensures exact metering, uniform colour development free of lumps, all whilst eliminating any residual product in the containers. Light-blocking technology Another plastic additive unveiled at drinktec is a novel light blocking technology for PET dairy packaging. "Lactra" from ColorMatrix is an opaque white liquid technology that ensures protection from UV and visible light at wavelengths up to 550nm, critical for extending shelf life in dairy applications such as milks, yoghurts and dairy beverages. Suitable for both single and multi-layer PET containers, it requires low addition rates. Whilst traditional opaque white colorant systems are typically dosed at around 20%, Lactra is used at an addition rate of only 6% to 8% for equivalent light- blocking performance because of ColorMatrix's latest generation liquid carrier system, "CoolRun". This advanced dispersion capability enables the optimisation of pigment particle size, to achieve maximum light reflection from minimal product. It also ensures highly stable processing, consistent colAir Max 1 Master