Pentel Sign Pen

The Pentel Sign Pen is a slender fibre-tipped pen, about the length of a pencil, its plastic barrel the same colour as its ink. The point is a short, firm bundle of acrylic fibres fed by capillary action from an ink reservoir inside the barrel, and it draws a line between that of a ballpoint and a brush. The cap carries a long, flat clip. The ink is water-based, so the line does not bleed through ordinary paper.

It was made in Tokyo by the company that became Pentel, founded in 1946 by Yukio Horie to make crayons and pastels for schools. In 1960 the firm had brought out an oil-ink marker with an acrylic-fibre tip, which wrote more finely than the felt-tipped markers of the day but soaked through the page. The Sign Pen, launched in 1963, put water-based ink in the same kind of point. Pentel calls it the world's first fibre-filled water-based pen.

At first it did not sell. Pentel took it to a stationery fair in Chicago, where a sample made its way to President Lyndon B. Johnson, who ordered a quantity to sign photographs with. The story was reported, and orders followed across the United States. Pentel says that in 1965 Sign Pens went aboard the Gemini 6 and 7 spacecraft, since the capillary feed needs no gravity. In Japan its name became the ordinary word for such a pen, used for every maker's version.

Pentel, which took that name in 1971, says it has sold more than two billion Sign Pens and that their appearance has hardly changed since. Model S520 is sold in Japan in eight colours, in a black barrel with a black cap for black ink and so on through red, blue, green and the rest, and in Britain in twelve, where it is now moulded partly from recycled plastic. It sells in Britain for about two pounds.