Editing Safety razor (section)

=== Single-edge razors ===
[[File:Vintage Gem Micromatic Safety Razor By The American Safety Razor Corporation, Single-Edge Blade, Twist-To-Open (TTO), Made In USA (28725926833).jpg|thumb|A Gem Micromatic single-edge razor and a packet of blades]]

The first safety razors used a single-edge blade that was essentially a {{convert|4|cm|abbr=on}} long segment of a straight razor. A flat blade that could be used alternately with this "wedge" was first illustrated in a patent issued in 1878, serving as a close prototype for the single-edge blade in its present form. New single-edge razors were developed and used side by side with double-edge razors for decades. The largest manufacturers were the [[American Safety Razor Company]] with its "Ever-Ready" series, and the Gem Cutlery Company with its "Gem" models. Although these brands of single-edge razors are no longer in production, they are readily available in antique trade, and compatible modern designs are being made. Blades for them are still being manufactured both for shaving and technical purposes.

A second popular single-edge design is the "Injector" razor developed and placed on the market by [[Schick (razors)|Schick Razors]] in the 1920s. This uses narrow blades stored in an injector device with which they are inserted directly into the razor, so that the user never needs to handle the blade.<ref>{{Cite web |url=https://books.google.com/books?id=xd8DAAAAMBAJ&dq=%22Popular+Mechanics%22+Jan+1935+floating&pg=PA491 |title=Inject Into Razor From Metal Clip" ''Popular Mechanics'', October 1934 |date=October 1934 |publisher=Hearst Magazines |access-date=16 March 2023 |archive-date=25 April 2022 |archive-url=https://web.archive.org/web/20220425231310/https://books.google.com/books?id=xd8DAAAAMBAJ&dq=%22Popular+Mechanics%22+Jan+1935+floating&pg=PA491 |url-status=live }}</ref> The injector blade was the first to depart from the rectangular dimensions shared by the wedge, standard single-edge, and double-edge blades. The injector, itself, was also the first device intended to reduce the risk of injury from handling blades. The Gillette blade dispenser released in 1947 had the same purpose.<ref>{{cite book | last = Krumholtz | first = Phillip L. | title = The Complete Gillette Collector's Handbook | year = 1992 | publisher = <!-- redundant with author name Phillip L Krumholtz - Is this self-published? --> | isbn = 0-9620987-2-8 | page = 457 }}</ref> The narrow injector blade, as well as the form of the injector razor, also strongly influenced the corresponding details of the subsequently developed cartridge razors. Both injector blades and injector safety razors are still available on the market, from antique stock as well as modern manufacture. The injector blades have also inspired a variety of specialised blades for professional barber use, some of which have been re-adopted for shaving by modern designs.

Until the 1960s, razor blades were made of [[carbon steel]]. These were extremely prone to [[rust]]ing and forced users to change blades frequently. In 1962,<ref name="wilkinson-history"/>{{sfn|McKibben|1998|p=58}} the British company [[Wilkinson Sword]] began to sell blades made of [[stainless steel]], whose edge did not corrode nearly so quickly and could be used far longer. Wilkinson quickly captured U.S., British and European markets. As a result, American Safety Razor, [[Gillette (brand)|Gillette]] and [[Schick (razors)|Schick]] were driven to produce stainless steel blades to compete. Today, almost all razor blades are stainless steel, although [[carbon steel]] blades remain in limited production for lower income markets. Because Gillette [[Defensive patent aggregation|held a patent on stainless blades but had not acted on it]], the company was accused of exploiting customers by forcing them to buy the rust-prone blade.<ref>{{cite news|url=http://www.time.com/time/magazine/article/0,9171,839192,00.html|title=The Blade Battle|magazine=[[Time (magazine)|Time]]|date=29 January 1965|access-date=2007-02-17|archive-date=21 December 2007|archive-url=https://web.archive.org/web/20071221190822/http://www.time.com/time/magazine/article/0,9171,839192,00.html|url-status=dead}}</ref>

The risk of injury from handling razor blades was further reduced in 1970 when Wilkinson released its "Bonded Shaving System", which embedded a single blade in a disposable polymer plastic cartridge. A flurry of competing models soon followed with everything from one to six blades, with many cartridge blade razors also having disposable handles. Cartridge blade razors are sometimes considered to be a generic category of their own and not a variety of safety razor.<ref>{{cite web | url = http://www.classicshaving.com/articles/article/590351/20879.htm | title = How to Use Your Double-Edge Razor | publisher = Classic Shaving | access-date = 16 September 2011 | archive-date = 26 September 2011 | archive-url = https://web.archive.org/web/20110926224432/http://www.classicshaving.com/articles/article/590351/20879.htm | url-status = live }}</ref><ref>{{cite web | url = http://today.msnbc.msn.com/id/6886845 | archive-url = https://web.archive.org/web/20100110053312/http://today.msnbc.msn.com/id/6886845 | url-status = dead | archive-date = 10 January 2010 | title = How to get that perfect shave | first = Corey | last = Greenberg | date = 30 January 2005 | work = Today | publisher = MSNBC }}</ref> The similarities between single-edge cartridge blade razors and the classic injector razor do, however, provide equal justification for treating both categories contiguously.

In 1974, [[Société Bic|Bic]] introduced the disposable razor. Instead of being a razor with a disposable blade, the entire razor was manufactured to be disposable. Gillette's response was the Good News disposable razor which was launched on the US market in 1976 before the Bic disposable was made available on that market.{{sfn|McKibben|1998|p=98}} Shortly thereafter, Gillette modified the Good News construction to add an [[Aloe vera|aloe]] strip above the razor, resulting in the Good News Plus. The purported benefit of the aloe strip is to ease any discomfort felt on the face while shaving.

In direct response to Wilkinson's Bonded cartridge, during the following year Gillette introduced the twin-blade Trac II. They claimed that research showed the tandem action of the two blades to give a closer shave than a single blade, because of a "[[hysteresis]]" effect. In addition to the cutting action of the first blade, it is also supposed to pull the hair out of the [[Hair follicle|follicle]] into which it does not fully retract before the second blade cuts it further. The extent to which this is of practical consequence has, however, been questioned.<ref>{{cite web |first=Cecil |last=Adams |url=http://www.straightdope.com/columns/read/174/are-twin-blade-razors-better-than-single-blade-ones |title=Are twin-blade razors better than single-blade ones? |publisher=The Straight Dope |date=25 November 1983 |access-date=2012-10-20 |archive-date=31 July 2010 |archive-url=https://web.archive.org/web/20100731053841/http://www.straightdope.com/columns/read/174/are-twin-blade-razors-better-than-single-blade-ones |url-status=live }}</ref>