Ballpoint pen

A ball point pen is a writing instrument, more specifically a pen, similar to a pencil in size and shape. The pens have an internal chamber filled with a viscous ink that is dispensed at the tip during use by the rolling action of a small metal sphere (0.7 mm to 1.00 mm in diameter); the ink dries almost immediately after contact with paper. Inexpensive, reliable and maintenance-free, they have largely supplanted the fountain pen.

History

The ball point pen was invented in 1938 by the Hungarian journalist Laszlo Biro, who noticed that the ink used in newspaper printing dried quickly, leaving the paper dry and smudge-free. He tried using the same ink in a fountain pen but found that it would not flow into the nib, as it was too viscous. Working with his brother Georg, a chemist, he developed a new tip consisting of a ball that was free to turn in a socket, and as it turned it would pick up ink from a cartridge and then roll to deposit it on the paper. An earlier patent on the same basic idea, dated 1888, was unused and expired. In addition, it has been argued that a design, by Galileo (during the 17th century), was that of a ballpoint pen.

In 1943 the brothers moved to Argentina and on June 10 filed another patent, and formed Biro Pens of Argentina. This new design was licensed by the British, who produced ball point pens for RAF aircrew, who found they worked much better than fountain pens at high altitude. Ball point pens are still widely referred to as a biro in many countries, notably Europe, Australia and New Zealand.

Eversharp, a maker of mechanical pencils[?] (and later the core of the now-Japanese company, Sharp Electronics) teamed up with Eberhard-Faber in May 1945 to license the design for sales in the US. At about the same time a US businessman saw a Biro pen in a store in Buenos Aires. He purchased several samples and returned to the US to found the Reynolds International Pen Company, producing the Biro design without license as the Reynold's Rocket. He managed to beat Eversharp to market in late 1945, and the pens were widely known as the rocket in the US into the late 1950s.

Similar pens went on sale before the end of the year in England, and by the next year in most of Europe.

Description There are two basic types of ball point pen: disposable and re-fillable. Disposable pens are chiefly made of plastic throughout and discarded when the ink is consumed; re-fillable pens are metal or plastic and tend to be higher in quality and price. The re-fill tends to be replacing the entire internal ink reservoir and ball point unit rather that actually refilling with ink.

The simplest types of ball point pens have a cap to cover the tip when the pen is not in use, but most pens have a mechanism for retracting the tip. This is usually controlled by a button at the top and powered by a spring within the pen apparatus, but other possibilities are two buttons, a screw, a slide, etc.

Multi-color pens have several fillings of differently colored ink inside, and one can select which one to move from its retracted position and use.

Early pens were notorious for leaking, but changes to the composition of the ink have largely made this a thing of the past. The major change was to include additives that make the ink normally much more viscous, but thin out under pressure. The pressure of ball inside the socket starts the ink flowing, but when the pen is lifted the pressure drops and the ink thickens again.