Ballpoint Pen Day

10 Jun
The invention of the ball point pen is celebrated on June 10.

Ballpoint pen
A ballpoint pen (also biro, and ball pen) is a writing instrument which dispenses a viscous ink from an internal reservoir through the rolling action of a metal ball at its point. This 'ball point' may vary in diameter, and may be made of brass, steel, or tungsten carbide.

Laszlo Biro, a Hungarian newspaper editor frustrated by the amount of time that he wasted filling up fountain pens and cleaning up smudged pages, noticed that inks used in newspaper printing dried quickly, leaving the paper dry and smudge free. He decided to create a pen using the same type of ink. Biro enlisted the help of his brother Gyorgy, a chemist, to develop viscous ink formulas for new ballpoint designs.
Laszlo's innovation successfully coupled ink-viscosity with a ball-socket mechanism which act compatibly to prevent ink from drying inside the reservoir while allowing controlled flow. Biro filed a British patent on June 15, 1938.
In 1941 the Biro brothers and a friend, Juan Jorge Meyne, fled Germany and moved to Argentina, where they formed Biro Pens of Argentina and filed a new patent in June 10, 1943.
Their pen was sold in Argentina as the Birome (portmanteau of Biro and Meyne), which is how ballpoint pens are still known in that country.