Lucia Buffoni: REPI additives can be ordered into three main groups, the first of which are those that are added to improve process performance; these include blowing additives, which are used to improve the blow-moulding process. The additive can be blended together with the colour and two main codes are available: one that is based on carbon black, and one based on another chemistry developed for bottles with very light shades. Then there are process-aid additives, which are used on the one hand to optimise preforms storage (normally by 5-10%) at the end of the injection-moulding process, and on the other to reduce static charges on the blowing line. The additive gravitates to the surface of the preform, so it does not stick to others. The result is fewer scratches among preforms, fewer scraps, and a higher productivity combined with a smoother blowing process.
One of the main requirements of a plastic container is the adequate protection of what's inside from external influences, such as UV and visible-light damage. Our range of UV absorbers provides such protection from visible light and UV rays even with lightweight packaging solutions, such as those for juices, vitamin waters or flavoured dairy products. We also offer acetaldehyde reducers that decrease the presence of acetaldehyde in the plastic, which typically results from the PET injection-moulding process and is also responsible for the unpleasant off-state of waters. REPI's reducers diminish acetaldehyde by up to 80%.
Finally, we have to consider recycling additives. REPI has a full range of anti-yellow additives able to enhance aesthetics of recycled PET (rPET), correcting the undesired off-state due to the different incoming material, which can have a greyish, greenish or yellowish colour. As a result, we obtain a betterlooking rPET product, thus, enabling converters to use increasing percentages of r-PET, making the packaging infinitely more sustainable. Our REPI IV-enhancer additive, meanwhile, acts on the mechanical properties of rPET, helping increase the IV, which typically has lower values than virgin PET.
Not only do we want our operations to be sustainable, but we are endeavouring to make them more environmentally friendly in the future. To that end, we are internally developing a carbon footprint scheme, which will be able to analyse each production step and calculate the CO2 impact of our processes. This, we think, will be useful for us in aiming for continuous improvement and will also give important information to our customers who need to select their suppliers not only from an economical point of view, but also in terms of choosing a 'sustainable partner'.
Our total quality management system offers an all-round support in monitoring the behaviour of our colours and, where necessary, adjusting their function instantaneously at any stage of production. It starts at the colour injection point, where the product is dosed by means of a dedicated unit - REPI's U2011 - developed and engineered specifically to interface with any kind of injection machine. Monitoring continues throughout the entire production process by means of the liquid colorant itself, since this is developed specifically so that not only does it not interfere but actually has a positive interaction with the client's own specific processes, parameters and conditions. Once it has been expelled from the machine, the preform can be checked immediately by the operator using the REPI Light Meter, a compact and portable instrument developed by REPI, which gives back a more reliable and consistent result than a visual check, without the need for specially trained staff. Lastly, the total quality management system comprises the REPI technical team travelling around and supporting customers with trials and validations, the start of industrial production and the training of operators.