Big.Dave said:
I was just wondering how long slants have been around and when did people start using them?
Just an assumption that DE razors started out with open comb, closed comb and then slant being the most recent innovation is this correct?
The OC was the first, and that was because it was easier to manufacture then a solid guard bar, Gillette introduced the Tech with a solid guard bar in 1939 (1938 in a "test market")
I'm just looking through a few books for a reply, so far the oldest reference I've found is an ad for a 1953 Slant (Hoffritz), less than a year later Gillette introduced colour coded TTO Superspeeds (Red and Blue), to combat the variability you could have with a slant. This led the way to the first "adjustable" in 1958.
From my limited knowledge, there are very few companies that made slants, and from what I gather, Gillette never made any slant models. (Hoffritz, Merkur did though)
A slant needs a solid guard bar to be functional, so I'd say early 50s sounds about right to me.
When I have a moment, I'll look a bit more into my reference books
edit: Thinking about it, a slant needs a fairly flexible blade, so it's first appearance can't be much earlier than late forties, early fifties, since "thin" blades were only introduced in the mid 40s.
Max