Francis J. Honn developed the highlighter at Carter’s Ink in Cambridge, Massachusetts. It went on sale in 1963 as the Hi-Liter.
The story began with complaints from parents. Carter’s had introduced its Marks-A-Lot markers in 1958, but the permanent ink was a problem when children drew on clothes and furniture. Parents wanted something they could wash off. The company’s chemists developed water-based inks for a range called Draws-A-Lot.
Honn joined Carter’s in 1959. He tried a yellow marker over some printed words. The words showed through the yellow ink. The yellow made them easier to pick out. He had found another use for the company’s markers.
Was it one person’s invention?
Honn recognised the use for marking text and helped get the product into shops. Carter’s chemists had developed the washable inks, and other staff helped with the launch.
To test demand, Honn asked sales staff to mark words such as “refund” and “free sample” in letters to customers. A note at the bottom told readers about Carter’s Reading Hi-Liter. Requests to buy it soon followed.
The company president suggested selling it through school bookstores. Carter’s already had the yellow markers, so it could use them for the new product. Honn later recalled that the rubber printing plate needed to add the Reading Hi-Liter name cost just $3.50.
When did the STABILO BOSS arrive?
The STABILO BOSS followed in 1971. Günter Schwanhäußer had seen American students marking text with coloured pens during a visit to the United States and wanted to develop a version of his own.
STABILO’s account also explains the broad, flat shape. Its designers were making models from plasticine when someone, frustrated with the results, struck one with their palm. The flattened model became the basis for the BOSS design.
Sources:
https://ed.buffalo.edu/magazine/issues/spring-2022/ed-artifact.html