Blacklight poster

A blacklight poster is a poster printed with inks which fluoresce under a black light. The inks used contain phosphors which cause them to glow when exposed to ultraviolet light emitted from black lights.

The 1960s gave birth to the pervasive use of illegal drugs mainly hallucinogenics such as LSD (lysergic acid diethylamide), mescaline, and marijuana. With the ability to glow and vibrate under ultraviolet light, the posters could simulate the sensations and visual distortions one experienced during an acid trip.

In the United States, blacklight posters emerged as part of the psychedelic fashion scene between 1967 and 1969. Since then, the art form has gone out of fashion and is generally viewed as a relic of the 1970s.

Although blacklight posters have continually been produced since the 1960s, there has been a resurgence in popularity since 2007 as blacklight and glow-in-the-dark parties have become more popular. As of 2014, there are five companies actively producing new and classic flocked blacklight posters in a wide range of content, including music, nature, and pop culture. The black parts of these posters are overlaid with black flocking, which gives it a velvet feel, and these are often referred to as velvet posters.

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Wikipedia