The History and Science of Erasable Pens

Are you tired of messy correction fluids and crossing out errors in your writing?

Erasable pens have revolutionized how we write, and this is how we got here.

From Pelikan’s early chemical ink eraser to Pilot’s groundbreaking thermosensitive ink technology.

We’ll explore the evolution of erasable pens and the science behind ink erasers, rubberized ink, and thermosensitive ink.

Discover how these different technologies work and how they allow us to erase our mistakes and rewrite.

1. The History of Erasable Pens

In the 1930s, Pelikan, a German pen manufacturer, developed a chemical ink eraser, marking the beginning of early attempts to create erasable ink pens.

In the 1940s, Eversharp introduced an erasable fountain pen, but it failed due to the ink’s tendency to smudge and fade quickly.

Pelikan launched the first commercially successful erasable pen with their Pelikan Tintentiger,

bleached ink. Once bleached, it could be written over with a special type of ink.

It was followed in 1979 by the Frawley Pen Company s Paper Mate Erasermate, which uses special rubberized ink and its eraser to remove the ink. You could now rewrite and correct your mistakes with the ink now erased.

The Erasermate was a huge success and remained unchallenged for over 15 years.

In 2006 erasable pens were revolutionized when The Japanese Pilot Pen Company introduced their Pilot Frixion Erasable pens using thermosensitive ink technology.

Today Pilot dominates the erasable pen market.

Check out our Ultimate Guide to Erasable Pens for more information.

2. The Different Types of Erasable Pen Technology

Erasable pens have revolutionized the way we write, making it easy to correct mistakes without the need for messy correction fluid or crossing out.

However, not all erasable pens are created equal, and different erasable pen technology works differently.

The following section will explore the science behind ink erasers, rubberized ink, and thermosensitive ink and how they allow us to erase our mistakes and rewrite.

2.1. The Chemistry of Ink Erasers: How They Bleach and Erase Ink

Ink erasers, also known as ink killers, use a chemical reaction to bleach the ink and make it disappear from the paper.

The active ingredient in ink erasers is sodium sulfite, an alkaline substance that reacts with the acidic ink to break down the dye molecules and make them colorless.

Usually, these inks are organic dyes, such as triarylmethane dyes, with a planar structure with stray electrons that visible light can easily excite.

The addition of negatively charged particles, such as the hydroxide ion or the hydrogen sulfite ion, causes a chemical reaction that changes the geometry of the dye molecule, disrupting the distribution of electrons and making the molecule non-planar.

This change makes the dye unable to interact with visible light and absorb specific wavelength ranges from the incident light, making the ink colorless.

To use an ink eraser, you apply it to the area of the ink you want to erase, and the bleaching solution reacts with the ink to make it disappear.

The ink eraser contains two felts, one containing the bleach solution and the other containing ink killer, a resistant ink for proofreading.

When you write over-erased ink, the ink killers-resistant ink on the second felt reacts with the paper fibers and fills in the gap left by the erased ink.

The ink you write over the erased ink can differ from the original ink, allowing you to correct mistakes or add new information to your writing.

2.2. Papermate Erasermate Pens Special Rubberized Ink Formula

The Papermate Erasermate pen is a unique erasable pen with a special rubberized ink formula.

This ink is made from a blend of materials, including polymers, resins, and other additives, giving it unique properties.

The ink designers made it soft and pliable so that the pen’s eraser tip could easily remove it from the paper.

Rubbing the eraser over the ink generates friction, heating the rubberized ink, which softens and becomes more malleable.

As a result, the ink adheres to the eraser, making it possible to lift it off the paper surface.

The designers made the rubberized ink to be easily rewritable.

After removing the ink, you can write over the same area without leaving any smudges or residue behind.

The ink adheres to the paper fibers uniquely, allowing it to be removed and rewritten without causing any damage to the paper or the pen.

2.3. The Science Behind Pilot’s FrixionPens: Metamo Ink and Thermosensitive Technology

Pilot Frixion pens use a specially developed thermosensitive ink called Metamo ink.

The ink contains microcapsules of a leuco dye, a color developer, and a color change temperature regulator.

The leuco dye determines the color but only produces it when it chemically bonds with the color developer.

The color change temperature regulator prevents bonding above a specific temperature, making the color disappear.

The ink’s temperature range had to be increased during development to make it commercially viable.

Pilot patented Metamo ink in 1975, but it took three decades to develop the Frixion series due to obstacles such as particle size and temperature sensitivity.

Introduced in 2006, The Frixion Ball pen, the first pen in the Frixion series, has an eraser designed to raise the temperature to over 60°C through friction without damaging the paper, which makes the ink disappear.

Low temperatures below ten °C can cause previously erased writing to reappear. Moreover, high temperatures can make the ink invisible without physically erasing it, which makes it unsuitable for legal or official documents.

Other companies are now trying to follow Pilot’s lead in this technology.

 The U.S. company Sanford which owns the Paper Mate brand, filed for a patent in 2015 for Irreversible thermochromic ink compositions.

It is for ink that will become permanently clear once it has become invisible due to friction.

How to Cleanly Erase Ink From Paper

3. How to Cleanly Erase Ink From Paper

If you want to erase pen ink from paper cleanly, there are several methods you can try. These include erasable pens, rubber erasers, using a craft knife, correction fluids, and household materials.

Check out our comprehensive guide for tips on effectively and cleanly erasing ink from your paper.

References

Paper Mate

Pilot

Pelikan

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Peter Warrior: Pen & Pencil Expert

With nearly a decade of experience in the pen industry, I successfully ran an online pen business for 9 years. My deep-rooted passion for pens and pencils led me to become a part-time blogger, where I've dedicated myself to sharing the wealth of knowledge I've amassed over the years. I'm a firm believer in the power of the written word, as echoed by Malcolm Forbes: "Putting pen to paper lights more fire than matches ever will." My expertise is not just rooted in business, but in the genuine appreciation and understanding of the art of writing instruments.

1 thought on “The History and Science of Erasable Pens”

  1. I am inventor of new writing inks, I would like to share my writing ink timeline with you
    1-1998, I invented low viscosity ball pen ink registered trade mark ButterGel ball pen ink.
    2- 2013, I invented oil gel ball pen ink “ButterGel Z”
    3- 2017, I invented an extremely smooth writing SuperJel ink for gel pen. It will replace all types of writing pen

    Reply

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