Although still a concept so far, Sidel claims to provide with its new stackable bottle, Stack & Pack, the first stacking solution of its kind for mid-size bottle capacities from 250 ml up to 1 L.
A deeper-than-usual concave indentation at the base of each bottle, realised through Sidel’s patented “stroke base” technology, enables efficient stacking. The neck of the bottle below fits into the base of the bottle above, significantly reducing the required amount of stacking space and eliminating any need for interlayers.
According to Sidel, the technology is up and running at its production facility and is ready for field tests at customers’ plants. The company also states that, when a customer buys into the concept, the bottles could easily hit the shelves in 2013.
The concept as such where a bottle, a big bottle, can be stacked is already on the market in Canada for Nestlé Waters, but for a bottle of the size of 500ml, or 1 litre, it did not exist.
The difference in manufacturing between the big and small bottles is that on bigger bottles it can be done by just blowing. The smaller bottles need a special step in the blowing stage to achieve that effect with the bottle. With bigger bottles it is just the mould where the shape of the bottom dent is incorporated to have the space for the cap. With a smaller bottle this is not possible.
Without disclosing any technology, Sidel states that it applies a patented step during the pre-form blowing process so that the space in the bottle is formed. It’s not standard blowing with the mould.
The, so called, Stroke-base technology also cuts blowing pressure by up to 10 bars during production. The reduction of blowing pressure using the stroke base solution during production generates energy savings.
Once the bottle is filled and capped, a stretch sleeve is wrapped around to form a pack of six bottles just like an elastic band. The compact stack enables 10 layers instead of six, to fit on a standard Euro pallet, increasing the number of bottles on a pallet by 40%.
Stack & Pack is suitable for sensitive products like juices, liquid dairy products, and milk.
Sidel claims, that while the stackable bottles could be produced in different shapes (including round bottles) and sizes, the surface area of square bottles offered strong branding potential. The stacking puts an end to crushed bottle necks.
But although more square bottles could be fitted on a pallet, Sidel notes, that there is a PET weight premium trade off vis-à-vis round bottles. What is gained on logistics thanks to packing and stackability will be upset slightly by the additional weight, and weight is a big issue.
This design of Sidel, reminded me of a student design back in 2010, when Andrew Seunghyun Kim, a student at the College for Creative Studies in Detroit, came up with design for an eco-friendly Coca-Cola bottle.
The environmentally responsible, rectangular bottle, which if empty, can be pressed like an accordion to 34% of its volume, features a bottle neck in one of the corners out of the middle, which facilitate pouring.
But what reminded me of this bottle was that Andrew came up (two years ago) with the same concept for stacking the rectangular bottles, as the neck of one bottle falls into the bottom of the other bottle.
Nice improvement in PET-bottles.
Note 1: As Sidel didn’t have photos available of the small bottles, I asked Andres Hutten Czapski, Project Manager at Sidel Canada Inc., to shoot some photos of the 4L bottle of Nestle Waters in Canada, which bottle is in the supermarkets. The principle of stackability is the same for the big and the small bottles. The detailed photos in this article show the Canadian 4L bottle. With many thanks to Andres.
Note 2: Notice the grip of the 4L Nestlé Waters bottle. The Deep Grip is the result of an industry collaboration between Plastic Technologies Inc. (PTI), French machine manufacturer Sidel, and consumer goods company Procter & Gamble (P&G). Last year I wrote about this development, see my article: “Deep Grip – Next Generation Large Container Handles”.