This shaving composition comprises a water soluble polyethylene oxide polymer having a molecular weight of 400,000 or less, a tracking agent component, a preservative component, and an anti-caking component.

From US patent 4,381,293

At some point I thought that shaving soap was a simple thing… well, I’ve learned much since then. And this 1983 patent for a shaving composition highlights just how much it can differ from a simple mixture of a base and fat or oil.

While the ancient Sumerian’s were satisfied with heating a mixture of wood ash and oil, George H Michel was a lot more specific. His shaving composition consisted of:

• 1-65% of a water soluble polyethylene oxide polymer of molecular weight of 400,000 or less.
• 20-80% of a trackability component – whatever that is.
• 0.005-7.5% of a preservative.
• 1-20% of anti-caking component.
• 0-20% of an humectant component.
• 0-10% of a lubricant component.

The whole thing were to be moulded into a solid form suitable for rubbing over the shaver’s face. It could also be moulded to a razor, as shown in Figure 2 of the drawing.

You can read the full patent on Google Patents if you like – personally I think I’ll go heat up some wood ash and lard.