Sidel works with Coca-Cola to launch new PET bottle design

Packaging machinery and solutions supplier, Sidel, has worked with the Coca-Cola Company (TCCC) to overhaul the bottle design of one of its best-selling soft drinks.

The new ‘spiral’ PET bottle for Fanta was created in order to differentiate the brand in the competitive carbonated beverages market.

“After years of success in the international soft drinks market, the Fanta Splash shape had effectively become owned by the carbonated soft drinks category rather than the brand. This is quite a standard occurrence over the life cycle of a brand which inevitably evolves over time.

“This meant it was the right time to redesign the bottle with an impactful shape to make it stand out once again on the shelves”, explained Gregory Bentley, Coca-Cola Packaging Engineer in charge of global project coordination.

The new bottle shape required precise understanding of how PET behaves under pressure, particularly with regards to how the carbonation of the beverage can potentially deform the bottle sections, which could lead to the drink spilling. Just like its predecessor, the new bottle was to be produced to be 100 percent recyclable.

The new PET bottle represents a “rule-breaker” in terms of bottle design for CSD (carbonated soft drinks), according to Sidel. It features a spiral, inspired by the twisting of an orange to release its juice. It is based on a series of ribs decorated with small bubbles, including a torsion in the bottom half. This spiral gives the Fanta bottle an unusual, asymmetric structure which presented a real challenge in terms of developing a container able to withstand deformation and stability issues.

“We were championing this spiral shape, which has the accolade of being truly unique in the world of carbonated packaging designs for containers in PET, and Sidel supported us to overcome the challenges that the design presented,” continued Bentley.

“It is definitively critical that all opposing sides of the bottle have the same developed length to avoid issues with perpendicularity,” explained Jérome Neveu, packaging expert at Sidel. “We optimised the grip profile and the angular base orientation to retain the bottle geometry once filled.”

The design continued to progress throughout the project - both from a brand marketing perspective and from a packaging performance point-of-view - to achieve the best solution.

The Spiral bottle required full design testing and refinement, achieved through more than 60 technical drawing iterations and FEAs (Finite Element Analysis) to test performance using computing analysis. It also involved the production of 15 pilot moulds and feasibility tests successfully managed with Sidel to achieve validation of the final bottle design.

Alignment of the label panel size and position was also part of the brief to ensure hassle-free changovers between Coca-Cola brands within bottling plants.

A similar bottle shape has been deployed for the whole Fanta bottle family and it is now available for 500 ml, 1L, 1.5L and 2L formats. When it comes to the 1.5L and 2L bottles, the Spiral design offers easier gripping and an improved pouring experience for the consumer.

A consideration throughout the development of the PET bottle was the capability to also transfer the new shape to the glass bottle, an objective which was also successfully achieved.

The new Spiral Fanta bottle in PET is sold in the UK and selected countires within Europe, with plans for global roll-out over the coming months.