One can tell an analogue human activity has become second nature when designers try to simulate it in the digital world. Computers and the more recent invention of touch-screen digital devices all come equipped with software which gives the user the ability to highlight text with bands of fluorescent colour. We may take the act of highlighting text for granted, but highlighters are pretty new, as proved by the fortieth anniversary this year of that most iconic of highlighters – the squat Stabilo Boss. It's a writing implement that wouldn't have seen the light of day weren't it for the invention of fluorescent inks and felt-tip pens and finally the frustration of its designer.
As a natural phenomenon, fluorescence was first noted and named as such in 1852. Man-made pigments, however, did not appear until the early 1930s when Bob Switzer of Ohio began mixing fluorescent minerals with wood varnish in his bathtub. Early uses were for magic tricks but the United States Army soon took notice and commissioned Switzer to combine his Day-Glo concoctions with fabric – soon the first high-visibility protective clothing was invented.
The availability of fluorescent printing inks during the early 1950s made them all the rage in advertising and graphic design. While technologically innovative, they were not received without reservation. Proponents vaunted their perceptual qualities claiming at least two hours added visibility at dawn and dusk. Detractors lamented the vulgar colours were just that and that they were no more than a cheap stunt to be had only at the expense of good design.
At this time the ink's ultraviolet glow and promise of imminent decay invited correlations with anxieties about nuclear catastrophe. But associations of fluorescence with radioactive activity were soon overshadowed by the emergence of counter-cultural movements in the 1960s that took on the bold, brash, brilliant colours as their own. It perfectly suited the purposes of youth rebellion – the sensory boost they offered provided a means of expression for drug-induced, mind-altered states and fluorescent hues were quickly attached to the art-nouveau inspired ornamentalism of psychedelic art.
In 1963 the Avery Corporation created the first "hi-liter" by introducing translucent ink pastel-coloured inks into the cartridge of a felt tip pen, invented by Yukio Horie of the Tokyo Stationery Company a year earlier. The first fluorescent pigment in luminous yellow followed a few years later. But the modern highlighter owes most to 1971. That's the year that German pen and pencil manufacturer Schwan Stabilo launched its Stabilo Boss highlighter, bringing fluorescence from counter culture to office culture and creating an iconic design in the process.
The Stabilo Boss is defined by a snub, flat, brightly coloured barrel with a black cap. It is said that the shape is the result of a frustrated in-house designer, given the daunting task of creating a revolutionary design for this brand new writing instrument, squashing the round-body clay prototype into his desk. And so the instantly-recognisable, squat trapezium was born.
Herein lies its genius, a round body lets a pen roll while a flat body plants the Stabilo Boss flush to the desk surface. It immediately sets it apart from other pens and can be recognised by touch alone. The grip required to clasp the Stabilo Boss is ergonomically conducive to the sidewards swipe of its slanted calligraphic nib, there are no variations on how to hold it as it simply won't let you. It is the shape of the Stabilo Boss which has made it so enduring. 60,000,000 units are produced every year and two are sold every second.
From the moment of their first manufacture, fluorescent pigments have been harnessed to everything from protection to provocation. The connection of these lurid colours to both counter-culture rebellion and the more studious activities involving a highlighter may seem unrelated. However, the highlighter pen is above all a tool for the act of reading and in the second half of the twentieth century, challenges to authority have been expressed with the empowerment of the reader, and the acknowledgment of reading as a productive force. How apt then that the Stabilo Boss has helped us mark our experience of the text in trails of luminous splendour. Mostly though, it tends to sit in our office drawers and slowly dry out.