Erasing in Reality, Erasing in Digital – A Design in the Life

Have you used pencils and erasers recently? I haven’t used an eraser for so long, I can’t remember the last time I used it. I bet many people reading this will feel the same way.

From what I hear, elementary schools in France use ballpoint pens and fountain pens instead of pencils. The same goes for exams, and they do that so students write their train of thought carefully.

The Practical Design of Erasers

Although I rarely use them these days, erasers as an item has an indescribable and mysterious charm, and I always find myself following its trend.

Here in Japan, the most common image that comes to mind when you think of erasers is the blue, black and white striped “MONO” erasers by a stationary company called Tombow. This blue, black and white combination is one of the few cases in Japan where a trademark has been registered for the color combination alone.

The MONO eraser first appeared in 1967, initially sold as a bundle with a pencil. It was not until 2 years later, in 1969, that it was released in the blue, black and white packaging that we see today. The design was done by Tombow’s in-house designer according to the MONO eraser history website.

The good ol’ MONO eraser (a cheap handy price of 100 yen, a little bit more than 1 US dollar)

Looking at the photo above, can you notice that the corners of this eraser package have been cut?

This manufacturing process is called “U-cut”, which probably started around the 00s, and is designed to make the eraser cover’s corners less likely to bite into the eraser and break. We don’t know whether it was some accidental innovation by someone that was spread and reflected to the product, or was a result of steady research and development.

A fresh new eraser has four sharp corners and is comfortable for precise erasing, but as you keep using it, the corners become rounded and it gets harder to erase with precision. In order to maintain the same erasing comfort, we had to make various efforts, such as using a cutter to sharpen the edges of the eraser.

That is why I was very surprised when KOKUYO, another stationary brand announced “Kadokeshi” (“kado”=corner, “keshi”=erase) which received an honorable mention in the 2002 KOKUYO Design Award.

The shape of “Kadokeshi” makes it easy to grasp and has many sharp corners for better erasing experience. Designed by Hideo Kambara.

This desire to keep erasing with sharp corners was embraced by many, and Kadokeshi became a bestseller for a long time. In addition, we are beginning to see erasers that take a different approach, such as gum-like thin erasers, which keep their corners in place.

METAPHYS vissis a spiral shaped eraser that always maintains a sharp corner even if you keep erasing. Designed by Chiaki Murata.

The Digital “Erasers”

Now, let’s take a look at erasers of digital tools.

For many people, perhaps the first encounter of the eraser on a digital tool may have been the Macintosh Paint tool. If you visit the Internet Archive, you can see the old Macintosh emulators and Apple II emulators running in your web browser that show the erasers back then. They can be found in the Paint Tools menu.

Internet ArchiveのMacintoshエミュレータで動作するMacPaint
MacPaint that runs on Macintosh emulators in Internet Archive
Internet ArchiveのApple IIgsエミュレータで動作するPaintWorks
PaintWorks that runs on Apple IIGS emulators in Internet Archive

Adobe Photoshop (Which is already more than just a photo processing tool) ‘s eraser offers a wide variety of brush-like erasing methods, as well as an eraser function that utilizes artificial intelligence.

The Artificial Intelligence-based eraser tool predicts and completes the erased area based on the surrounding image and the general image to make an image appear that was not there (see: Removal of Objects by Content-Sensitive Fill). Notice that the eraser is no longer “erasing” but in fact “creating” something.

 The menu bar of the eraser tool from the latest version of Photoshop

For digital content, it is easy to erase and redo. You can take bigger jumps and make more casual tries since you can always undo. It is strange that the concept of the “eraser” continues to be used as a metaphor even today, when digital tools have evolved so much and now with basically unlimited storage capacity.

And while the eraser in real life has never changed over decades and seemingly reached its perfection, “Kadokeshi” proved that there is still room for evolution. This makes us wonder what becomes of digital erasers when they still are dragging the old concept now.


In “A Design In The Life” series, we will provide hints on improving the resolution of the design experience from the perspectives of both design in daily life and design in digital space. If you have a topic you would like us to cover, please let us know.

Written By

Yukio Andoh

Yukio is an UX Designer, UX Writer, Design Sprint Master. He has worked on a wide range of projects from web design, information appliances, smartphone applications, VR systems, giant stereoscopic dome theaters, digital signage, and media art. He loves movies and science fiction novels, and is buried in books in his everyday life.

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