Button copy

A highway distance sign in Oklahoma using button copy

Button copy is a type of physical design for road signs in the United States. Round plastic retroreflective buttons made of transparent plastic are placed in rows following the contours of sign legend elements, usually painted white, such as letters, numbers, arrows, and borders. In daylight, the buttons visually blend with the white sign legend elements and so are minimally conspicuous. At night, light from each approaching vehicle's headlamps strikes the retroreflective buttons and is reflected back towards the eyes of the vehicle's driver. Thus the sign is made sufficiently conspicuous and legible for adequately fast and accurate recognition and interpretation by drivers.

Button copy on a letter, arrow, and route marker from a sign in Los Angeles

Button copy is now rarely manufactured. It has been supplanted by a newer technology: retroreflective sheeting made by various manufacturers in numerous colors and grades.^[1] As state departments of transportation increasingly stopped specifying button copy signs in favor of signs made with sheeting, it became uneconomical to maintain production of the materials and supplies for making button copy signs. The last state to specify button copy signs was Arizona, which switched to sheeting in 2000.^[2]

The advantage of button copy is durability, in that a well-made button copy sign has a service life of around 40 years.^[3] In contrast, signs made out of retroreflective sheeting are expected to last only around 15 years.^[3] However, at night, retroreflective sheeting is clearly visible and readable at much longer distances than button copy.^[3]

Button copy overhead sign on I-270 in Ohio, including button copy shield outline and numerals
Button copy overheads at I-71/I-76 interchange in Ohio, showing reflection of button reflectors in camera flash
Button copy sign on US 30 in Ohio, showing reflection of buttons in letters, shield numerals and outline, and arrow
At night, the retroreflective buttons on these overhead signs in Seattle, Washington are often lit up by light sources (such as a vehicle's headlamps) to ensure easier reading
A rare button-copy Mexico Federal Highway 15 guide sign formerly located after the Mexico-U.S. border crossing in Heroica Nogales, Sonora, Mexico. Mexican highway signage generally has neither featured button-copy nor Highway-Gothic lettering on its highway signs.