The photocopier, copier, or copying machine, as it is variously known, is a staple of modern life. Copies by the billions are produced not only in the office but also on machines available to the public in libraries, copy shops, stationery stores, supermarkets, and a wide variety of other commercial facilities.
Over the years, various processes have been employed. By far the most common type of photocopier today is the electrostatic, or xerographic. It is the type most people are familiar with, and arguably that with which most people associate the term photocopier. It was the electrostatic process that revolutionized copying as a part of everyday life. The modern photocopying era began in 1960 with the introduction of the Xerox 914, the first push-button, plain-paper copier. Within one year, sales doubled, and Fortune magazine called the 914 ‘‘the most successful product ever marketed in America.’’
While ‘‘photocopying’’ to most people means copying with the degree of the quality and speed that has existed since the 1960s, copying technology in a rudimentary form can be dated to the pantograph of the seventeenth century. The Standard of the later eighteenth century was a copying machine patented by James Watt in 1780. It was a device more accurately known as a copying press, and consisted of a mechanism for exerting pressure on a dampened sheet of tissue placed over the document to be copied. Written with ink based on gum arabic or sugar, the image on the original was transferred to the tissue copy, albeit in reverse, when the two sheets were interfaced under pressure. The reason for the tissue was so that the copy could be viewed correctly looking through it from the back.
A copying press that Benjamin Franklin brought back to the U.S. from Europe was apparently one of this type. George Washington was known to have had two copying presses. Thomas Jefferson, a prolific letter writer, made copies of his correspondence using a copying machine he considered not only ‘‘a most precious possession’’ but ‘‘the finest invention of the present age.’’ Jefferson first used a copy press and then a pantograph, or ‘‘polygraph’’ as his was known. The polygraph was a mechanical apparatus that used wires and movable wooden arms holding a pen or pens to duplicate, on a separate page or pages, the motion of the human arm writing out the original. One of the earliest U.S. patents was for a device of this kind—a ‘‘machine for writing with two pens’’ patented in 1799 by Marc Isambard Brunel.
An advantage to the polygraph was that it made exact (not image-reversed) copies on plain paper, the same paper as the original if desired. But the polygraph was a delicate, fragile mechanism that was difficult and clumsy to use.It was versions of the copying press, rather than the polygraph, that generally became the Standard of nineteenth century. Besides being simpler to use, the copying press could be made small and rugged enough to be easily transportable, and it was sometimes used by travelers.
A device known as the electric pen, patented by Thomas A. Edison in 1876, led to the most common form of copying machine of the early twentieth century. Developed as part of Edison’s automatic telegraph, the electric pen, working at a rate of roughly 8000 pulses per minute, could make minute perforations in the form of letters or drawings on a stencil. A plain sheet of paper was then placed under the stencil, and ink was pressed through with a roller, making exact copies, albeit in small quantity. This led to the mimeograph machine, the mainstay of copying over approximately the first half of the twentieth century. At first, copies were made by hand, one by one. The rotary mimeograph, which was introduced by A.B. Dick in 1904, made copies automatically using a revolving cylinder, at a great increase in speed. The photostat process, using a special camera to produce an image directly on photosensitized paper without going through a negative, was developed in the early twentieth century. Photostats remained a common way of copying documents until the coming of the modern photocopier. A shortcoming of the photostat, in comparison to the photocopier, is that it was not ordinarily consumer-operated technology. Do-it-yourself copiers suitable for the small office began to appear in significant numbers by the 1950s. Ordinarily, photosensitized paper was required. Some processes worked with a liquid and others with fumes, and still others with infrared rays to produce heat by which the image was transferred to photosensitized paper (thermography). In general, copies were clearly identifiable as such, the paper usually having a sheen and glossy feel unlike, and inferior to, modern plain-paper copies.
Meanwhile xerography, the principal modern form of photocopying, was also under development.
Generally speaking, xerography (from the Greek xeros meaning ‘‘dry’’) uses a dry powder as opposed to ink or liquid chemicals. Static electricity attracts and bonds the powder to form an image on paper, and heat then makes the bond permanent. When xerography came into use, it was generally only for large office applications. The first commercial XeroX Copier (then spelled with a capital X at the end) was introduced in 1949 by the Haloid Company. It was based on a 1938 invention of Chester Carlson. Haloid later became Haloid Xerox and subsequently Xerox Corporation. The first XeroX was messy and difficult to use. Most of the process was carried out manually, and it often misprinted. By modern standards, it was also a notoriously slow process. At an early demonstration, according to one newspaper account, observers timed the operation at 45 seconds per copy.
In 1960 a vastly improved model, the Xerox 914, was introduced, and with it the modern era of photocopying. The push-button 914 worked automatically and printed on plain paper as opposed to the less-desirable photosensitized paper. However, it weighed 290 kilograms, limiting its use to largeoffice applications. Its bulky size notwithstanding, the 914 caught on quickly and revolutionized photocopying. Modern xerographic copiers, produced by a number of manufacturers, are available as desktop models suitable for the home as well as the small office. Many modern copiers reproduce in color as well as black and white, and office models can rival printing presses in speed of operation.
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