Double edged cartridge razor

Or, perhaps more correct, a double double edged cartridge razor. Which sounds both weird and pointless, but stay with me here.

Invented by Sergio Somonetti, and assigned to Warner Lambert Co LLC, the double edged cartridge razor strikes me as a typical transitional device. It looked like a traditional safety razor, yet used the recent idea of cartridges. And since Sergio suggested using two blades in each cartridge, it became a double double edged cartridge razor.1

The razor looked more or less like most double edged razors do. Perhaps the head is a little bigger than most, and the handle of a somewhat odd shape. But overall it don’t stick out like a sore thumb when it comes to looks.

Sheet one of the patent drawing for the double double edged cartridge razor
Sheet one of the patent drawing for US patent 3,777,396
Sheet two of the patent drawing for the double double edged cartridge razor
Sheet two of the patent drawing for US patent 3,777,396

As can be seen from the drawings, the top cap and base plate don’t come apart. Instead they form, along with the blades and a spacer, the cartridge. The blades looks like modified DE-blades.2 As can be seen a series of perforations have been added to each blade. Along with cut-outs in the bottom plate and spacer, these allowed lather to exit the razor.

As for the why? Part of the raison d’etre for the invention was likely to lock the shaver into a single source of blades. In other words, to create a walled garden – something I don’t like when it comes to shaving. The reason given in the patent, however, is different:

An advantage of bonded blade cartridges is that it is possible to optimize the shaving angles defined by the relationship between the cutting edges and the guard bar surfaces to minimize the possibility of nicks and cuts and to maximize shaving efficiency.

From US patent 3,777,396

Yes, there is a theoretical possibility that changing a blade in a regular safety razor can lead to variations in shaving angles. If the razor is made with very lose tolerances, that is. In a razor made with a minimum of quality control? Not really – even my cheaper-than-a-cup-of-coffee Yuma3 maintains a consistent blade geometry. Consistently less than ideal, but consistent none the less.

So why did the double double edged razor fail? In part, I believe, because it didn’t look different enough from a regular double edged razor. By trying to look traditional, it managed to look old fashioned. By retaining the reasonable large head needed for a double edged blade, it missed out on the one benefit early cartridge razors offered; a smaller head that were easy to manoeuvre.

The full patent can be read at Google Patents. If you enjoy old razor and shaving patents, why not check out And if you enjoy me snarking on old razor and shaving patents, I got a long list of posts where I do just that.


  1. Try saying that ten times fast.
  2. The slit down the middle is a dead give away to the inspiration behind the blades.
  3. The photos in the linked review seems to have evaporated when I moved my blog between hosts a couple of years ago.

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  1. Pingback: Double edged cartridge razor - Razors n Blades the shave that saves

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