Calligraphe Calligraphy book 4 books + 1 pen + 10 refills + pen holder

Magic calligraphy ink typically works through a chemical reaction with carbon dioxide (CO2) in the air, and it usually takes 24 to 72 hours to fade completely. 

How the Ink Works

The "magic" in disappearing ink relies on a change in the ink's chemical composition, most commonly an acid-base reaction involving a pH indicator. 

• Initial State: The ink is an alkaline solution, containing a pH indicator dye (such as thymolphthalein) and a basic substance like sodium hydroxide, which makes the ink appear colored (often blue or purple).
• The Disappearance: When the ink is exposed to the air, the sodium hydroxide reacts with carbon dioxide in the air to form carbonic acid. This reaction lowers the pH of the ink solution.
• Other Mechanisms: Some disappearing inks may also be heat-sensitive (thermochromic) or photosensitive (light-sensitive), fading when exposed to heat or UV light, respectively. 

How Long It Takes to Fade

The fading time for this type of ink is not instantaneous and depends on environmental factors, particularly humidity and the concentration of CO2 in the air. 

• Typical Range: Marks generally disappear within 24 to 72 hours under normal conditions.
• Faster Fading: Blowing on the ink, which adds carbon dioxide from your breath, or placing the paper in a more acidic environment can speed up the process.
• Slower Fading: High humidity or a sealed, low-CO2 environment can slow the reaction and make the ink last longer.
• Reappearance: The color change is sometimes reversible; for certain formulations, applying an alkali (like an ammonia solution) can bring the color back temporarily. 

Due to their temporary nature, these inks are primarily used for handwriting practice (e.g., in reusable calligraphy copybooks), fabric marking in sewing, or novelty purposes. They are not suitable for any kind of permanent documentation. 

Calligraphy book 4 books + 1 pen + 10 refills + pen holder