Tecnología

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Estadisticas Gratis

50 aniversario de la xerocopia

From one man's kitchen chemistry, a huge industry began.

Fifty years ago, Haloid Co., a small Rochester, NY, firm in the Photography business brought out a new office copying machine that it dubbed XeroX. The market reception was any thing but enthusiastic. The equipment was complex and cumbersome to operate. Practically nobody wanted the machine.

Ten years later, after spending millions of dollars on further development, the company finally introduced a new, improved copier. Office copying was revolutionized. The company was launched on a wave of dramatic growth.

The Xerox process was the brainchild of an intense, innovative, persevering inventor, Chester F. Carlson. Carlson was born in Seattle in 1906. His father was an arthritic, itinerant barber. His mother was frail and died of tuberculosis when he was 17. By the time CarLson was 14 and living in San Bernardino, CA, he was the chief support of his family, working before and after school hours and on weekends as a janitor and later as a printer's devil (odd job assistant). For a while, he had a weekend job in a chemical laboratory. He managed, nevertheless, to put himself through college, spending two years at a junior college in Riverside, CA, and then earning a degree in physics at the California Institute of Technology.

The year was 1930; in the depths of the Great Depression, jobs were scarce. He found one at Bell Telephone Laboratories but was laid off. Then he got a position in the New York City patent office of P. R. Mallory Co., a manufacturen of electrical equipment. At night, he earned a law degree at New York Law School. Working as a patent attorney for Mallory, he became frustrated by the inconvenience of getting copies of the documents he needed. Projection photographic processes were available, but they required costly, time-consuming equipment and the resulting copies (photostats) were expensive. Documents could be duplicated by mimeograph or by offset printing; these, however, required a specially prepared stencil or mat and were only practical when dozens of copies were wanted. Banks of typists, working with messy carbon paper, did most office copying.

Carlson decided there must be a better way. He believed that conventional photographic methods where impractical because they were too slow and inconvenient. Studying in his spare time at the New York Public Library, he became intriqued by photoconduttors, materials whose

conductivity is altered when they are exposed to light.

He began experimenting ,ghts and on weekends in the en or a closet of his apartmen. He used sulfur, which occasionally caught fine while being melted and created noxious fumes, being him very unpopular with is neighbors. He moved his experiments to a small room behind a beauty parlor and above a bar in Astoria, Queens, New York. Meanwhile, he hired Otto Kornei, an unemployed physicist recently arrived as a refugee from Germany, to help him. On October 22, 1938, the two coated a metal plate with sulfur and wrote "10-22-38 Astori'a in ink on a glass sude. The metal plate was charged electrostatically, then exposed to bright light passing through the sude. The sulfur-coated plate was sprinkled with a dye that clings to charged surfaces. The loose dye was blown off the plate and a piece of wax paper pressed against it and then heated. "10-22-38 Astoria" appeared on the paper. Car1son and Kornei repeated the experiment several times to convince themselves that it really worked and then went out for a modest lunch to celebrate.

Carlson applied for patents for his electrostatic process; being a patent attorney, he made sure that the coverage was tight and comprehensive. His patents are considered classics. Then, realizing he did not have the means to commercialize the process, he set out to interest companies operating in the office equipment business. He contacted more than 20, including IBM, RCA, Remington Rand, and Eastman Kodak, over a four-year period. He was met, he recalled later, "with an enthusiastic lack of interestf Admittedly, the images he produced were often fuzzy and smudged.

In 1944, though, a representative of Battelle Memorial Institute, a nonprofit industrial research organization in Columbus, OH, happened to be visiting Mallorys New York office. Carlson told him about the invention and showed him a few copies. The Battelle man carried this information back to Columbus. Carlson was asked to demonstrate what he had done and Battelle soon made a deal. It would invest $3000 in developing the idea further in retum for 60% of any royalties that might come out of it. Cartson had no choice but to agree.

Probably BattellŽ s major contribution to the development was the use of amorphous selenium, which is much more sensitive to light than either the sulfur or anthracene that Carlson had worked with, as the photoconducting material. This development made fast copying possible.

Carlson had called his process "electrophotography", which didnŽt appeal to Battelle. A professor of classical languages at Ohio State University suggested "xerography", from the Greek words for "dry" and "writing", and the term stuck. It also is known as the transfer electrostatic process.

In 1946, Joseph C. Wilson was named president of Haloid at the age of 36, succeeding his father; his grandfather had been a cofounder of the ñrm. Haloid was a small producer of photographic paper and photocopying equipment and supplies. It had thrived during World War II selling special photographic paper to the armed forces. But now business had slumped. In Rochester, the company Uved under the shadow of Eastman Kodak. Wilson, a forward-looking young executive, asked his research chief, John H. Dessauer, to screen the technical and patent literature in search of something new that the company might pursue. Dessauer noticed an article in a technical journal describing Battelle's work with xerography. He and Wilson visited Columbus, were impressed, and in 1947, Haloid obtained rights to commercialize the process in exchange for royalties. Haloid funded Battelle's research at $25,000 a year.

Three years later, Haloid was ready to market its first xerographic copier. It was an immense contraption, actually three separate machines, complicated to operate, requiring two or three minutes to make a single copy. Around Haloid's offices it was known as the "Ox Box". It had few takers. Unexpectedly, though, it was found to make good paper masters for offset printing presses. During the next 10 years, Haloid came out with a few other xerographic devices. None of these, however, were in great demand.

Haloid continued to plug away at simplifying and fine-tuning its copien It plowed $88 million into its efforts, much more than it was earning. It borrowed heavily and sold stock to raise enough funds. In 1955, it obtained full title to CarlsonŽs patents from Battelle in exchange for 50,000 shares of stock plus royalties. At one time, discouraged, it offered to sell its rights to xerography to IBM. IBM would have none of it. Finally, in 1959, the company had a machine that it thought might find buyers. By then, it had changed its name to Haloid-Xerox.

In the machine, light projected off the original document falls on a drum coated with amorphous selenium that has been electrostatically charged. The charge is dissipated where the light strikes but remains in the image areas. A charged ink powder (toner) then flows across the drum and is attracted to where the selenium remains charged, thereby forming an image of the original. A piece of ordinary paper then is charged and pressed against the drum, picking up the charged ink, which then is bonded to the paper when heated.

Concerned about its capacity to make and market its new machine, Haloid-Xerox proposed a joint venture with IBM. IBM undertook a copier market study. The results were unfavorable. The copien was too big and too expensive. Demand would never top 5000 machines. IBM brushed off xerography once again.

By then, as well, the office copien business had become crowded. More than 30 different copier machines were available.

The biggest seller was the Thermofax, introduced in 1950 by Minnesota Mining & Mfg. (3M). It was based on the thermographic process discovered by Carl S. Miller while he was studying for a Ph.D. in physical chemistry at the University of Minnesota in 1940. After he obtained his degree later that year, Miller went to work for 3M, doing research on pigments. But he continued to investigate his thermographic copier whenever he could find time. By 1944, he had put together a crude machine that he showed to 3M's director of research, who was sufficiently impressed to turn Miller loose on the project full time.

Thermography uses a sheet of papen containing a ferric compound and a phenolic compound that form a colored image when exposed to heat. This sheet is placed on top of the document to be copied, and intense infrared light is shone on it; the light is absorbed by the ink on the original, generating heat, which is transmitted back to the heat-sensitive thermographic paper to form a copy.

Ranking second to 3M's Thermo-fax was Eastman Kodak's Verifax copier, based on a gelatin transfer process. It requires a light-sensitive sheet of paper coated with a gelatin emulsion containing a variety of chemicals, including a silver halide, a dye formen, and a developer through which light is passed to produce a negative image of the original placed above it. This image can then be transferred to a sheet of sensitized copy paper and developed. Eastman Kodak's Verifax machine hit the market in 1953.

Several other companies were offering copiers in the late 1940s and early 1950s that were based on light-sensitive papers containing silver halides that produce a negative from which copies could be developed. Machines were also available based on the diazo process using UV light and papen made with diazonium compounds that form azo dyes. Although diazo machines were primarily used for copying engineering and architectural drawings, some served as office copiers because copies cost only a fraction of those made by other methods.

All these processes had serious shortcomings, however, including special copy paper, which could be expensive. In fact, the machine makers typically earned more from selling supplies than from the copiers themselves. Diazo machines could only copy documento that were transparent or translucent and they required a source of high-intensity UV light. In all of the silver halide processes, the copy had to be developed using inconvenient wet chemicals and carne out of the machine damp. Thermography worked only with documents that had inks that absorb infrared radiation; the treated papen tended to darken when exposed to low heat, and the copies were often flimsy and became brittle.

The Haloid-Xerox Model 914 (socalled because it could handle documente measuring up to 9 x 14 in.) also had some drawbacks when it was introduced in 1960. Compared to most other copiers, it was big, somewhat bigger than a desk. And it was expensive. In fact, initially the company decided to tease the machine rather than sell it, at a monthly minimum charge of $95. That could be a deterrent for small offices that needed fewer than 100 copies per day. (When the company started to sell its copien in 1963, the price tag was $29,500; it cost less than $2500 to make.)

But the machine made highquality copies automatically and rapidly, with just the touch of a button, using a completely dry process on any kind of ordinary paper. Demand was strong. Haloid-Xerox had optimistically expected to tease 1000 copiers the first year; it actually shipped 2000. By the end of 1962, 19,000 were in use, churning out, on average, 120,000 copies a year each.

A smaller version of the machine, the desktop model 813, was brought out in 1963. By then, the company (now known simply as Xerox Corp.) was riding high. Its sales, which had been just $33 million in 1959, had jumped to $170 million. (Carlson had retired to upstate New York with Xerox stock worth more than $20 million plus royalty income.)

Competition, however, soon raised its ugly head. Some firms in the early 1960s started making machines based on a direct electrostatic or electrofax process, which was quite similar to the xerography process. These, however, used a special copy paper coated with zinc oxide and dyes that had to be developed after exposure. They did not make much of a dent in the market. In the 1970s, IBM and later Eastman Kodak introduced copying machines that did cut into Xerox s position. Still later in the 1970s, Japanese producers, notably Ricoh and Canon, begin marketing copiers that were cheaper, smaller, and more reliable. Xerox s market share eroded severely during the 1980s to well under 20%.

Today, Xerox is a solid $20 billion firm that manufactures copiers, laser printers, and publishing equipment. But its glamour days of the 1960s are a memory.

David M. Kiefer, assistant manag. editor of Chemical Engineering New; until his retirement in 1991, is a con sulting editor for Todays Chemist al Work.