Pencil is a stationery and painting that was originally made of pure graphite. The writing is done by scraping the graphite onto the media. However, pure graphite tends to break easily, too soft, dirty effect when the media rubbing by hand, and get your hands dirty when held. Because it is then created a mixture of graphite with clay so that the composition harder. Furthermore, the composition of the mixture is wrapped with paper or wood.
Pencil History
The use of lead and graphite has been started since the time of the Greeks. Both give the effect of gray streaks, although a little more black graphite. Graphite is very rarely used until later in 1564 found to contain large amounts of pure graphite in Borrowdale, a valley in the Lake District, northern England. Although it looked like coal, minerals can not be burned, and shiny black scars, and easily removed over a writing surface. At this time the term graphite is still confused with tin, lead, and Plumbago, meaning "like lead" since it is almost the same. Hence the term lead pencil (pencil lead) is still used today. Because texture is oily, chunks wrapped in sheepskin or small pieces of tin berbentuktongkat bandaged with a rope. No one knows who first had the idea to incorporate the black lead into wooden container, but in the 1560's, primitive pencils had reached the European continent.
Shortly thereafter, lead mined and exported to meet the demands of artists; and in the 17th century, can be said to lead has been used everywhere. At the same time, pencil makers experimented with black lead to produce better stationery. Pure and easily extracted, lead from Borrowdale became the target of thieves and black marketeers. To overcome this, the British Parliament passed a law in 1752 which stipulates that could lead thief jailed or exiled to a penal colony.
But in 1779, a chemist Carl W. Scheele researched and concluded that graphite has a much different chemical properties with lead. Graphite is pure carbon molecular composition software. Finally in 1789, geologists Germany, Abraham G. Werner gives the name of graphite, which is derived from the words Yunanigraphein, which means writing. Thus, the contents of a pencil instead of tin.
Pencil development
Over the years, British monopolize graphite pencil-making industry because it was pure enough to be used without further processing. Because the European graphite was inferior, pencil factories there to experiment with different ways to improve the content of a pencil. French engineer Nicolas-Jacques Conté mixing powdered graphite with clay, forming the mixture into sticks, and burn it in the fireplace. By varying the ratio of graphite to clay, he could make leads that produce various shades of black-processes used until now.
In the 19th century, the manufacture of pencils into a big business. Graphite is found in several places, including Siberia, Germany, and is now called the Czech Republic. In Germany and then in the United States, a number of factories opened. Mechanization and mass production drove the price, and at the beginning of the 20th century, even school children using a pencil.
Initially given a graphite pencil torn wrapping paper suit the wearer. But later found to be more practical and efficient way to envelop entire graphite rod with two wooden slats ditoreh to provide a place for graphite rod and then put together.
Pure graphite artist may be preferred due to its characteristics is more straightforward. But for everyday use, required a lower quality graphite to be more flexible. In 1795, French chemist, Nicolas Jacques Conté, discovered by mixing graphite with clay in order to produce a better pencil and practical. One of its derivatives are pencil Konte.
On March 30, 1858 Hymen Lipman of Philadelphia, Pennsylvania, United States patent pencil with eraser tip. But then the patent is canceled by reason sebanenarnya no new invention of the pencil case. Mechanical sharpener in 1880 and quickly became very popular.
modern processing
Pencil in the modern era was made by crushing pure graphite and clay into powder form. The mixture is then given water, dianginkan, and then burned for three days. Then the leads that have been molded into the shape of a long and thin coated with fine wood.
Originally created in pencil more square shape due to limited production machine. But in the modern era, more rounded shape encountered more comfortable. However, still many who like shape pencil grip angle because it gives a more robust and easier to control when writing.
characteristics
In contrast with pens, pencils tend to give the impression of gray and color are weak and rupture compared with the pen that gives a solid color and sharp. Pencils are also more easily removed than the pen.
Some pencil eraser to be accompanied by practical reasons. Pencil is very liked student. However, most professional artists who give priority to quality will be more like a pencil without an eraser, eraser is doubtful considering the quality and frequency of removing the larger will make erasers that are too small to be quickly wasted.
identity
Pencil differentiated according to the composition. Letter B informs thickness (boldness), which means more graphite content. While the letter H inform violence leadnya composition, which means that the content of the clay more. Pencil with mark F means the composition is apt to diraut up to a maximum kurtosis. While the numbers in front of the letter shows the thickness or composition of a pencil hardness. For example 2H going harder than H, or 2B will be softer and thicker than B. HB pencil has two properties means hard and thick.
Color pencil shows the production area. Factories in North America to give yellow, Germany and Brazil gave green. India and parts of Asia to give black and red. Switzerland gives the red color.
While the British gave yellow and black. Most of these color standardization Faber-Castell created producer. But many manufacturers who do not follow this standard.
Pencil type in the modern era
Advances in materials and manufacturing technology makes many kinds of pencils that can be found in the market according usefulness of each. Among others are:
• Pencil lead
• pure graphite pencils
• Mechanical Pencil
• Colored pencils
• Konte
• Pastel in the form of a pencil
• Dermatograf
Modern pencil
Pencil now is tuilis tools and sophisticated image at once versatile, which is annually produced worldwide to billions rods. Pencil can make a 60-kilometer line and write 45,000 words. Fill mechanical pencil, which stems from metal or plastic, does not need diraut. Instead of graphite, colored pencil containing dyes and pigments in dozens of colors.
reference
• Steve Ritter. Pencils and Pencil Lead. Also published as an article in Science & Technology, What's That Stuff ?. Volume 79 No. 42. October 15, 2001. ISSN 0009-2347
• Early Office Museum. History of the Lead Pencil
• WWW.id.wikipedia.org
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