Ballpoint pens have a tiny ball made of brass, steel, or tungsten carbide as their writing tip. A compartment called the ink reservoir holds the ink, and a narrow tube links the reservoir to the ball. The ball, which is fitted into a socket, turns as it rolls across the paper, carrying ink from inside the pen onto the paper. Many ballpoint pens have a plastic cap that helps prevent ink from drying out on the ball. On others, a push-button mechanism draws the pen point into the body of the pen.
Most ballpoint pens depend on gravity to pull the ink to the ball. For this reason, ballpoint pens generally do not write well when held sideways. However, some ballpoints are designed so that slight pressure is always applied behind the ink column. This design enables the ink to move constantly forward and the pen to write even when its point is higher than its back end. Ballpoint pens use a thick, sticky ink because a thinner ink would leak out around the ball. But the use of such ink makes ballpoint pens write less smoothly than most other pens.
Fountain pens have a somewhat triangular writing point, called a nib, which is made of gold or stainless steel. A system of narrow tubes known as the feed carries the ink from the pen’s reservoir to the nib.
Fountain pens use a highly fluid ink. They rely on a property called capillarity to draw the ink into and through the feed. Capillarity causes the inner surface of the tubes to attract molecules of ink. These ink molecules, in turn, attract other ink molecules, and the feed fills with ink from the pen’s reservoir.
The feed in a fountain pen also includes a number of air passages that lead to the reservoir. These passages allow air to fill the top of the reservoir as ink is drawn from the bottom. Thus the air pressure inside the pet remains equal to the air pressure outside the pen, and the ink flows easily. If the air pressure inside the ink reservoir is lower than the atmospheric pressure outside, the ink will not reach the point and the pen will fail to write. However, if the air pressure over the ink column becomes greater than the air pressure outside the pen, ink will flood out from the front of the pen. To avoid such flooding, fountain pens are designed with a collector. The collector, which is located near the nib, consists of a series of fins and spaces that provide enough additional room to accommodate forward moving ink.
Soft-tip pens, also called porous-pointed pens, have a relatively soft writing tip. Some soft-tip pens, called felt-tip pens, have a felt-like writing tip. The tip of others is made of absorbent plastic. Soft-tip pens use fluid, brilliantly colored inks. The reservoir in a soft-tip pen consists of a special synthetic material made up of many fibers. This type of reservoir, called a capillary reservoir, holds ink in much the same way that a sponge holds water. During writing, the absorbent tip of a soft-tip pen continually draws ink from the reservoir onto the paper.
Roller ball pens combine certain features of ball point, fountain, and soft-tip pens. Like ballpoint pens, roller ball pens have a tiny ball that turns in a socket at their tip. But unlike ballpoints, roller ball pens use highly fluid inks, which allow them to write as smoothly as soft-tip and fountain pens.
Roller ball pens may have either a capillary reservoir similar to that used in soft-tip pens or a reservoir like that of ballpoints. A wick made of an absorbent material draws ink from the reservoir and carries it to the ball. The wick can carry only a limited amount of ink at any onetime. In this way, the wick regulates the flow of ink and prevents it from leaking out.
Specialty pens are designed for specific purposes. for example, artists and mechanical drafters use a pen called a technical pen. This pen comes with a set of interchangeable pen points of varying widths. Another special pen, called a lettering pen, is used to create an elegant style of handwriting called calligraphy.
2007-01-03 00:42:56
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answer #1
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answered by amoxi7 3
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There's a tube filled with fast-drying ink. At the bottom of the tube is a ball that is in a socket. The top of the ball is coated in ink. As you move the pen (roll the ball), the ink is transferred from the ball to the paper.
The ball seperates the ink from the paper and keeps the air out of the ink.
If you've ever used roll-on deodorant, it works the same way.
2007-01-03 00:43:40
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answer #3
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answered by Ray D 2
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well, i know that ball point ink pens have a tube inside them, and at the bottom of the tube of ink there is a silver ball. the silver ball is half in the pen, and half sticking out of the hole in the pen (where you write from) when you write it rotates the ball and each time it moves it gets covered in ink from the inside. and when you write this keeps repeating the process allowing you to write? haha... hope that helps! its kinda like those lipglosses with a ball at the top of them.....
2007-01-03 00:44:57
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answer #4
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answered by christine 3
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Blue ink and black ink are considered "Official". You can sign checks and official documents with either colors. So, I guess, just because they are used so much, people are used to them and blue is easily discenible in a book (if you take notes) from the print.
2016-05-22 22:34:57
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answer #5
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answered by Anonymous
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