Mondo Knows Facts
Ballpoint pen ink thins temporarily under rolling shear stress
Thixotropic ink paste liquifies around revolving pen balls and dries instantly
Ballpoint pen ink is formulated as a thixotropic paste using synthetic dyes suspended in oil or glycol solvents. As the rolling metal ball rotates against paper, mechanical shear stress momentarily thins the thick ink into a smooth liquid layer before it instantly dries on the page.
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Tags: pens, ink, physics
Ballpoint pen ink thins temporarily under rolling shear stress: the short answers
- Where does this come from, and can I check it?
- Thixotropic ink paste liquifies around revolving pen balls and dries instantly. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a everyday life fact?
- Yes. It sits on the Everyday Life shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
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