1. Pencils do not contain lead. Why are they called pencils?
The name "pencil" originates from a misunderstanding when people discovered "lead" more than 400 years ago. At that time, people did not know the composition of graphite. The traces it smeared were much darker than the usual lead, so they called it "black lead" and used this material to make pencils.
2. Is pencil lead poisonous?
In fact, pencil lead is not toxic, and the main raw materials for making pencil lead are graphite and clay, so pencil lead is non-toxic.
3. Why do I have to use a 2B pencil to draw the answer card in the exam?
This is because the machine card reading uses optical character recognition technology, which is based on the concentration of carbon or graphite and the size of the blackened area.
The darker the pencil, such as 3B, 4B, 5B, 6B, the softer the refill, the easier it is to break;
The darker the pencil is, the harder it is to erase, which may pollute the answer cards. Moreover, the more graphite content is easily attached to other answer cards along with the paper, affecting the identification of other answer cards.
The unified use of 2B pencils is also convenient for management and prevents candidates from making special marks with special pens.
4. Why are pencils mostly hexagonal in shape?
The round pen is the most comfortable to hold, but the round pen is easy to roll and break, and the hexagon just meets the two conditions at the same time;
From the perspective of technology, regular polygons or circles are easy to process, and asymmetrical sections are time-consuming and laborious without aesthetic feeling;
From the perspective of saving materials and space, it is best to cut the pencil section "continuously", and hexagon is the most reasonable choice.
5. China's first pencil factory
In 1935, Wu Tangmei returned to Shanghai from Japan to study abroad and raised funds to establish a pencil manufacturer, China Pencil Factory No. 1. This is also the first pencil manufacturing factory in China that can make lead lead, pencil holder and appearance. The pencil produced is later known as "Zhonghua Pencil".
6. The first pencil factory in the world
In 1662, the first pencil factory in the world was built in Nuremberg, Germany.
7. 101 The Origin of Pencil
The "Zhonghua" 101 high-grade drawing pencil, which was born on the eve of National Day in 1954, is the first high-grade drawing pencil in China. The model is named "101", implying a gift for National Day 10.1. In the 1970s, it was recognized by the Shanghai Light Industry Bureau that the quality of the pencil has surpassed that of the Venus brand pencil in the United States. It has become the most vigorous and popular pencil in China.
8. The world's largest pencil
The largest pencil in the world was born in the hands of a carpenter named Ashlita in the United States. It is said that this pencil is an amazing 23 meters long, almost as long as a train carriage. It can be said that even if it is written for a lifetime, it can not be written, so it also won the Guinness World Record.
