Straight razors with open steel blades, also commonly known as cut-throats, were the most commonly used razors before the 20th century. Straight razors consist of a blade sharpened on one edge. The blade can be made of either stainless steel, which is slower to
hone and
strop, but it is easier to maintain since it does not stain easily, or high carbon steel, which hones and strops quickly and keeps its edge well, but rusts and stains easily if not cleaned and dried promptly. At present, stainless-steel razors are harder to find than carbon steel, but both remain in production. The blade rotates on a pin through its tang between two protective pieces called scales: when folded into the scales, the blade is protected from damage, and the user is protected. Handle scales are made of various materials, including mother-of-pearl, celluloid, bone, plastic, and wood. Once made of
ivory, this has been discontinued, although fossil ivory is used occasionally.
Disposable blade straight razors (known as shavettes) These razors are similar in use and appearance to straight razors, but use disposable blades, either standard double-edged cut in half or specially made single-edge. These shavettes are used in the same way as straight razors, but do not require stropping and honing. == Safety razors == The first step towards a safer-to-use razor was the guard razor – also called a straight safety razor – which added a protective guard to a regular straight razor. The first such razor was most likely invented by a French cutler Jean-Jacques Perret circa 1762. The invention was inspired by the
joiner's plane and was essentially a straight razor with its blade surrounded by a wooden sleeve. The earliest razor guards had comb-like teeth and could only be attached to one side of a razor; a reversible guard was one of the first improvements made to guard razors. An early description of a safety razor similar in form to the ones used today is found on
William Samuel Henson's 1847 patent application for a comb tooth guard. This guard could be attached to a straight razor or to a razor "the cutting blade which is at right angles with the handle, and resembles somewhat the form of a common hoe." Around 1875, a new design with a smaller blade placed on top of a handle was marketed by the
Kampfe Brothers as "the best available shaving method on the market that won’t cut a user, like straight steel razors."
Removable-blade razors The term safety razor was first used in 1880 and described a basic razor with a handle attached to a head where a removable blade may be placed. The edge was then protected by a
comb patterned on the head to protect the skin. In modern-day safety razors, the comb is now more commonly replaced by a safety bar. There are two types of safety razors, single-edged and double-edged. The single-edged razor is essentially a long segment of a straight razor. The double-edged safety razor is a razor with a slant bar that can be used on both sides, with two open edges. The blade on the double-edged safety razor is slightly curved to allow for a smoother and cleaner shave. In 1901, the American inventor
King Camp Gillette, with the assistance of William Nickerson, submitted a patent for a new variation of safety razor with disposable blades, which was patented in 1904. One reason was that shaving with a safety razor should be safer and more convenient than shaving with a classic
straight razor with a sharp blade. The thick grip of these safety razors can be reused. Gillette realized that a profit could be made by selling an inexpensive razor with disposable blades. This has been called the
razor and blades business model, and has become a very common practice for a wide variety of products. Many other brands of safety razors have come and gone. Much of the competition was based on designing blades that would fit only one style of razor until the blade shape was standardized by the inclusion of a multi-faceted central channel to the blade which would accommodate the various designs of blade securing systems; e.g., three pins, a slender metal bar, etc. Even today, these various securing forms still persist in their variety in DE razors, all accepting the same universal blade design.
Cartridge razors Exploiting the same razor and blades business model as pioneered in the early 20th century, cartridge razors were developed in the 1960s and are now the most common form of shaving in developed countries. Although designed to have a more
ergonomic shape at both the handle and head (including commonly a pivoted head which keeps the blades angled to the skin at a predetermined angle through the shaving motion), the concept is very similar to that of the double-edge razor. However, here, the entire head assembly (a cartridge) is removed and disposed of, not just the blade. It is also common for these cartridge heads to have multiple razor blades set into them, commonly between two and five blades. In 2023, US-based retailers sold 20 percent fewer razor blades than in 2019.
Disposable safety razors Disposable safety razors are highly similar in design to cartridge razors, constructed from inexpensive materials (most commonly injection molded polycarbonate), yet are meant to be wholly disposable after use with no blade sharpening or replacement possible. One device was invented in 1963 by American entertainer and inventor
Paul Winchell.
Lifespan Safety razor life may be extended by drying the blades after use. == Electric razors ==