Erasable ink used in erasable ball-point pens is a gooey substance that looks like tar. Scientists from The Paper Mate Company invented it by combining ink with rubber.
The advanced rich black ink formula wipes away cleanly and pressurized to fluidly write at any angle.
This is a special ink used in a new kind of ball-point pen called the Erasermate. This pen erases, like a pencil, making it easy to correct mistakes. The word Erasermate in and of itself has become known as the erasable pen of the Papermate product line.
To get this thick stuff out of the pen, a special refill was built. Erasable ink dries slowly and could be rubbed off before it hardens. After about 24 hours, the ink dries, and the writing becomes permanent.
Erasermatecomes in blue, black and red ink, with the pen’s exterior often matching the color of its ink.
The Erasable ink used in erasable ball-point pens took over a decade to develop and needs slight pressurization for continuous flow during use.
A positive result of this pressure is that writing is possible through a wider range of paper to pen angle than with non-erasable ballpoint pens.
In 1979/80 Papermate introduced two retractable versions of the Erasermate; called the TW200 and TW400, they carried retail prices of $7.50 and $9.50 respectively.
The TW name was possibly used to signify “twist”, as both the ink cartridge and the eraser would retract by twisting the pen tip, which clicked into place when fully exposed. To close, the user would twist it the other direction hiding the ink and eraser inside the pen’s body.
Each black pen has a precise yet bold 1.0mm medium point. There’s even an eraser on the cap for quick erasing and a convenient clip to secure your erasable pen.
Content for this question contributed by Tina Olson, resident of Marinette, Wisconsin , USA