PETpla.net Insider 01+02 / 2010

BOTTLE MAKING 16 PET planet insider Vol. 11 No. 01+02/10 www.petpla.net The first foamed PET bottle from Coca-Cola in Denmark We had already seen the first foamed PET bottle from PTI at the NPE, and at the drinktec exhibition Coca-Cola showed us the practical application that they are running in Den- mark, which prompted us to go back to PTI and ask them about the current situation with regard to this new bottle. normal bottles - there is no need for the bottle blower or filler to invest in new technology. Of course the pre- form manufacture is rather different. Here the plasticising unit is fitted with the MuCell gas injection proc- ess so that the foam can be intro- duced into the preform. It is possible to produce 100% foamed bottles where up to a 5% lightweighting can be achieved, but PTI believe that the main require- ment will be for 2-layer bottles. Here, unlike the classic multi-layer proc- ess, the first component is injected, then the preform is transferred to a second mould and the second com- ponent injected over the first. At Coca-Cola the inner layer is solid, as we mentioned above, and the outer layer is foamed. However the opposite can also be achieved, with a foamed inner layer and a solid outer layer. This gives the opaque bottle a very high quality gloss. Additives for specific purposes, such as colours or scavengers, can be included in the different layers. However in many cases light-blockers are unneces- sary, or can be significantly reduced, because the foam already blocks 50% of the light falling on the bottle. The following practical applications may be seriously considered: CSD Here, for the first time, opaque bottles can be produced without an additive, so that they are fully recycla- ble. And the density can be precisely adjusted by the solid inner layer to ensure that the PET flakes can be separated from caps and labels in the sink/float process during recycling. The foamed outer layer also helps keep the beverage cool for a longer time. Foamed PET bottles for CSD: without additives and fully recyclable PET and PTI go together like peaches and cream. For more than 25 years, PTI have been paving the way from the resin to the bottle and today many of the big names in the beverage business turn to PTI when it comes to developing a new bottle. PTI’s latest development is the foamed PET bottle, suitable for all kinds of applications. PTI Vice Presi- dent Frank Semersky has launched the new technology with the name oPTI. The first practical applica- tion can now be seen on the store shelves. Coca-Cola are testing the bottle on the Danish market. “For the soft drinks sector it is important that the bottle can be recycled, so despite the foam we have to watch that the density of the material is still higher than water in order that the flakes from the foamed bottle sink like ordinary flakes during the sink/float separation process,” explained Frank Semersky. “The CSD bottle has a solid core and, as a second stage, a foamed outer layer. The foam gives the bottle a silvery opaque look without the use of addi- tives,” he continued. The stretch/blow process and the machines are the same as for