Nearly forty years ago now I had a chat with a cutlery retailer in Liverpool who specialised in supplying the many chefs in the city. He told me that Sabatier knives were the best and that they came with two kinds of blade. The carbon steel blades were for professional chefs, they were much sharper but demanded far more care, if they were left wet they would quickly rust, for instance. The stainless steel blades were for housewives, easy to look after but not capable of taking the same sort of edge as a carbon blade.
Now, of course, it has all changed. Chefs use stainless steel knives and Sabatier are no longer the pre-eminent brand.
The safety razor industry invented by King C. Gillette at the beginning of the 20th century had a novel business model, known as bait and hook. The razor itself sold at a loss to use the price elasticity of demand mechanism to get the maximum number of customers on board. Once they had bought their razor they needed a constant supply of the patent protected blades which sold at a big profit. This business model has been imitated by other industries, notably the video game console industry, where the basic console is often sold at a loss, but its manufacturer makes a big profit on every game sold. Other users of this business model are the cellphone industry and the computer printer industry.
With Gillette’s model the shorter the life of a blade the more money he made, so he made the blades of carbon steel which would rust very quickly. Maybe requiring a new blade every day. Of course you can stop the rust by removing the blade from the razor and keeping it in a bath of alcohol, but who can be bothered? So it came as a revolution in 1960 when the British firm, Wilkinson Sword, introduced stainless steel blades that lasted much longer. This forced all the other blade manufacturers to do the same and the carbon steel blade was dead (nearly). According to Wikipedia stainless razor blade steel is: a martensitic stainless steel with a composition of chromium between 12 and 14.5%, a carbon content of approximately 0.6%, and the remainder iron and trace elements.
If you want to try an old fashioned carbon steel blade today you still can. Treet in Pakistan make two types the “Blue Special” are in fact black and the “Dura Sharp” are the same blade with a PTFE coating. These are very easily available online from Amazon, eBay or specialist retailers like Connaught. Because they are different to stainless steel blades some people don’t like them at all. Other people think they are fantastic. These carbon steel blades really divide opinion amongst DE shavers, so they are well worth trying just to find which side of the fence you are on.
In the 1970s Personna tried to move the razor game on with the famous 74, made of tungsten steel. But by lasting around 10 times as long as a stainless steel blade it destroyed the basic business model of the industry so it died a natural death.
So where now? We are spoiled with many different manufacturers of excellent DE blades from around the world. The technology for making these to a high quality at a low price has been mastered. In fact there is no excuse whatsoever for a bad blade. But still we are stuck with the old business model and it is possible to make blades a lot better than what we now use. The main problem is productionising new technology in order to hit price points that consumers will accept.
I have already written about the ultimate blade, by using the hardest substance, diamond, and placing every atom in the optimum place it is possible to make a blade that will last 1,000 times longer than stainless steel whilst being sharp enough to split hairs. But it will be difficult to make a viable business model out of this.
There is a technology that is somewhere between steel and diamonds. That technology is ceramics. Kyocera in Japan make kitchen knives out of zirconia (this has a hardness of 8.2 mohs compared with steel at 5-6 mohs and diamond at 10 mohs) , which holds its edge ten times longer than steel and which is impervious to corrosion. They even make an electric machine for sharpening these, a technology that could be adapted to razor blades. However these blades don’t bend which makes them incompatible with most current DE razors. So whilst there is potential here we are unlikely to see it. And when an enthusiast tried to make his own ceramic cut-throat razor he couldn’t get it to work.
Kyocera themselves have looked at the possibility and this is what they have to say about it:
How come you don’t make a shaver?
Too dangerous! A metal razor blade has a relatively “rounded” edge (under the microscope) which prevents the blade from cutting into the skin. A ceramic razor blade, however, does not have a rounded edge and slices into the skin. Thus, a ceramic shaver would be too dangerous to use. Several engineers in Sendai who tested prototypes can confirm this painful fact!
So there you have it. Looking at the reality it seems that the technology of the blades we use for DE shaving is stuck in a rut. The only viable way out would be if someone had another go at making tungsten steel blades, but in artisan like quantities.