A Blaze of Crimson Light: The Story of Neon
Gas discharge tubes showing the colors produced by different noble gases. Left to right: xenon, krypton, argon, neon, and helium. (Wikimedia)
Like Hampson in England, Carl von Linde in Germany, and others, Parisian electrical engineer and inventor Georges Claude applied the Joule-Thomson effect to liquefying air, scaling up the process to produce huge quantities (up to 10,000 cubic meters per day). With his former schoolmate and colleague Paul Delorme, he formed a company in 1902 named simply L’Air Liquide that expanded rapidly to become a multinational corporation. While selling liquid oxygen for industrial purposes, Claude carried out scientific research. At first, he had hoped to discover additional noble gases by analyzing large volumes of liquefied air, but he was forced to admit that “after Ramsay there was nothing more to be done.” His next project combined the leftover neon from his liquefaction of air with his dislike of the overwhelming brightness of electrical lighting at the time.
Lines of Light
Claude was not the first to look to gas tubes for light. Spurred by the commercial success of Thomas Edison’s incandescent lightbulbs, inventors attempted to transform gas-discharge tubes into practical lighting systems. In the late 1890s Daniel McFarlan Moore, a former Edison employee, filled 10-foot glass tubes with nitrogen or carbon dioxide under low pressure, adding electrodes at both ends. These “Moore lamps,” which glowed bright white when electrified, were more efficient than the carbon-filament incandescent bulbs then in use. Though the lamps were used as general lighting in some stores and workplaces, they were expensive to install (a “glass plumber” had to connect the tubes on-site), required high-voltage electricity, and tended to leak. After 1910, when improved incandescent lamps with tungsten filaments displaced Moore’s tubes, his company went under.
Claude soon found that adapting Moore’s concept to neon involved more than just switching gases. His tubes gave a magnificent glow, but impurities set free from the hot electrodes quickly dimmed the brightness. A carbon filter solved that problem but not the issue of metallic buildup around the electrodes, which made the tubes flicker out too soon. Claude installed larger electrodes that stayed cooler: the resulting tubes burned brightly and steadily, with 20-foot tubes lasting as long as 1,200 hours.
Successful at last, Claude filed his first patent for neon lighting in 1910. That December he demonstrated his invention at the Salon de l’Automobile (the Paris Motor Show). Inside the exhibition building thousands of incandescent bulbs studded light fixtures and manufacturers’ signs, glinting off the shining metal of the cars below. Outside, two 40-foot neon tubes glowed a vivid orange-red on the building’s colonnade. Modern technology of all sorts was on display: the newest cars and the newest lighting made possible by the electrical network then spreading rapidly throughout Paris.
Claude admitted that red neon was not ideal for general lighting but insisted there were some situations in which neon would prove superior, such as for illuminating monuments and in advertising, where “the more dazzling and attractive a light, the more suitable it is.” This last use turned out to be the most popular. In 1912 Claude installed the first-ever neon advertising sign in a Parisian barbershop on the Boulevard Montmartre. A large rooftop sign for the Italian vermouth maker Cinzano soon followed, along with illumination for the entrance of the Paris Opéra. Making the most of his new invention, Claude formed another company, Claude Neon, to sell franchises for neon signage. Despite a high price tag—$100,000 plus royalties—dozens of franchises opened around the world, especially in major American cities. Neon was on its way to becoming a household name. Though the earliest neon signs were relatively simple—the range of colors and animation would come later—business owners competed with each other to trace their signatures on buildings and rooftops. Claude’s signage monopoly lasted through the 1920s, eventually crumbling as his patents expired and former employees leaked his trade secrets.