On right: photo of Kirin Fire can from Christian Kadluba’s Flickr Photostream

“Fire” is a canned coffee — one of a number of products from Kirin that are packaged in a faceted “diamond cut” can. More familiar to consumers in Japan, this is a type of can that Toyo Seikan has been manufacturing since 2001.

Comparing its pattern to some other soda cans we’ve considered in the past — the 1966 harlequin patterned Coke cans and Jorge Ubeira’s series of hand-bent Diet Coke cans — one might reasonably wonder whether there is something geometrically inherent in cylinders that makes this pattern particularly suitable for cylindrical packaging.

As it happens, Toyo Seikan’s “diamond cut” can pattern derives from research at the “Institute of Space and Aeronautical Science” in Tokyo: Koryo Miura’s 1969 paper, Proposition of Pseudo-Cylindrical Concave Polyhedral Shells.

As Toyo Seikan’s own website states:

The three-dimensionally structured truss (triangular framework structure) design, called a “PCCP shell” (Pseudo-Cylindrical Concave Polyhedral Shell), was developed during the process of space engineering research. It was incorporated into the can processing technology to produce diamond cut cans.

Miura’s insight was that the roughly geometric patterns that naturally occur on the sides of compressed or “buckled” cylinders are not simply “failed forms,” but rather, “the basic forms of a new shell which could function superbly…” — and recognized that the basic pattern which cylinders naturally tended to exhibit (when axially compressed) was the “Yoshimura pattern.”

Professor Y. Yoshimura had previously noted the geometric characteristics of buckled cylindrical shells in his 1955 paper, On the mechanism of buckling of a circular cylindrical shell under axial compression for the National Advisory Committee on Aeronautics:

“The reason why the cylindrical shell reveals such a particular behavior for buckling will be attributed to the geometrical features of its deformation, that is, to the fact that a developable surface quite different from the original cylindrical surface can exist. On the basis of these fundamental concepts concerning deformation and energy, the mechanism of the buckling can be understood more completely.”

…and he then went on to describe what is now known as the “Yoshimura pattern.”

Yoshimura Pattern

via: Bravis International

Getting back to the “diamond cut” cans, it’s interesting to note that “due to equalization of pressure, the pattern becomes more distinct when the can is opened.”

While many have marveled at this practical application of aerospace technology to quotidian soda-can packaging, the fact is, that seamless beverage cans were an important part of the research from the very beginning.

(More about pseudo-cylindrical concave polyhedral packaging, after the fold…) [Read more…]