Rollerball pen
A rollerball or engl. roller ball pen is a writing instrument that emits a water-based ink over a writing ball similar to a ballpoint pen . In contrast to ballpoint pens, whose oil-based writing paste has a high degree of toughness, the ink in the rollerball is thinner, which enables easy, gliding writing.
Two systems are offered:
- Ink rollerball : system that combines the advantages of a fountain pen and the easier handling of a ballpoint pen.
- Gel pen : system whose gel-like writing color ( gel ink ) flows more easily than that of a ballpoint pen, but at the same time is water-insoluble and is usually document-proof according to ISO 14145-2.
history
The first (ink) rollerball systems were developed in 1963 by the Japanese pen manufacturer Ohto. The ink feed and ink were in a closed case that resembled a ballpoint pen refill.
With the Ink-Liner system developed by Karl Meisenbach KG in 1995 , the ink feeder and writing ball no longer had to be exchanged, only the standard ink cartridge .
technology
Writing tips
Common materials are stainless steel , nickel silver or plastic (mostly POM ) for the frame and hard metal or ceramic for the writing ball. The ball diameter is usually between 0.5 and 1.0 mm, with products down to 0.17 mm (especially in Japan ) available.
Ink supply
There are two systems for ink storage - fiber storage and free ink:
Fiber storage: the older and simpler design. The ink is held in a capillary reservoir made of polyester fibers and transferred to the writing tip via a fiber rod (ink feeder). Since the larger capillaries are first emptied with less holding force when writing, the flow of ink decreases as the pen becomes more empty.
Free ink: Here the ink is available unbound in a tank, but has to be dispensed via a control system that prevents uncontrolled leakage. Written out ink is replaced by air in the tank, and when the temperature or air pressure changes, the expansion of the air drives the ink out of the tank. To prevent it from leaking at the writing tip, a stack of plates is placed in front of the tank, in the interstices of which such excess ink is collected. Since the air can only flow into the tank through capillary slots in the plates, the ink is pumped back into the tank when the air in the tank contracts again. In the core of the stack of plates (usually a single injection-molded part ) there is an ink feed that connects the tank with the writing tip. The advantage of this design is an even ink release and complete writing of the ink contained in the pen. However, this system is not present in all rollerballs, so that some e.g. B. start to expire on flights in aircraft with pressurized cabin . During cruise, the pressure is set to about 2,000 m cabin pressure altitude, which means that the pressure in the pens is usually higher during the flight. Some manufacturers also explicitly offer “flight-safe” pens.
Countries of origin
The largest manufacturers are in Japan, where this type of pen was developed in the 1960s (major manufacturers are Pilot , Uniball and Pentel ). In addition, China has established itself as a major manufacturer.
Individual evidence
- ↑ Ceramic Ball. (No longer available online.) Ohto Co., Ltd., archived from the original on March 18, 2012 ; accessed on April 12, 2014 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ The breakthrough came with the "Ink Liner". Chamber of Commerce and Industry Darmstadt, accessed on October 8, 2019 .
- ↑ Why do some pens leak in airplane cabins or at high altitude? ( Memento from March 22, 2014 in the Internet Archive )
