What does a pencil mean?

1564, a black mineral-graphite was discovered in a place called barodale, England. Because graphite can leave traces on paper like lead, and its color is much darker than lead, people call it "black lead".

history

At that time, shepherds in Barodale often used graphite to mark sheep. Inspired by this, people cut graphite blocks into small strips for writing and painting. Soon, King George II of England simply owned the Barodale graphite mine to the royal family, making it an exclusive product of the royal family. Writing with graphite strips will not only dirty your hands, but also break them easily. 176 1 year, the German chemist Faber first solved this problem. He washed graphite with water to make it into graphite powder, then mixed it with sulfur, antimony and rosin, and then made this mixture into strips, which were much tougher than pure graphite strips and less likely to get his hands dirty. This is the earliest pencil.

Be distributed

Until the end of 18, only Britain and Germany could produce this kind of pencil in the world. Therefore, after Napoléon Bonaparte launched a war against neighboring countries, Britain and Germany cut off the supply of pencils to France. Therefore, Napoléon Bonaparte ordered the French chemist Comte to look for graphite ore in his own country and then make pencils. However, the quality of French graphite ore is poor and its reserves are small. Comte mixed clay with graphite and put it in a kiln for barbecue, which made a good and durable pencil lead in the world at that time.

proportion of ingredients

Pencil lead produced by different clay proportions in graphite has different hardness and color. This is the origin of H (rigid pencil), B (soft pencil) and HB (pencil with moderate hardness) marked on pencils today. The task of putting a wooden stick coat on a pencil was completed by American craftsman Monroe. He first built a machine that could cut the battens, then carved a slot in the battens, put pencil lead in the slot, and then aligned and glued the two battens together, with pencil lead tightly embedded in the middle. This is the pencil we use today.

use

Pencil is a writing tool made of graphite or colored clay, which is used for study, office, engineering drawing, art, painting, various marks and so on. In ancient Greece and Rome, lead bars similar to pencils were made of lead metal. This kind of pen is mostly made into a cone shape, and lead is rubbed on other objects, leaving traces of lead for marking. /kloc-in the 0/4th century, a similar modern pencil appeared in Europe, and Dutch painters used it to draw on paper. Italians use a mixture of lead and tin to make lead strips, which are used for painting and writing. 1565, German C. Gesner's library made an illustration with a pencil, which recorded that "for drawing and taking notes, people used lead and other mixtures as refills, and then attached wooden handles to draw lines ...". In the same year, Britain began to make the most primitive wooden pencils by hand, with graphite as the refill. 1662, the world's first pencil factory-Shidelou pencil factory was built in Nuremberg, Germany.

new technology

176 1 year, F. Caster, a German, founded Faber Caster pencil factory in Nuremberg. The lead core was made by heating sulfur, antimony and other binders and mixing them with graphite, which made the pencil manufacturing technology take a big step forward. From 1790 to 1793, N.J. Kant of France used the method of washing graphite for the first time to improve the purity of graphite, and bonded graphite with clay to make a refill. This method is called Kong Defa. Kant pencil factory was established in 1793, which laid the foundation of modern pencil industry.

Chinese pencil

China established the first Dahua pencil factory in Kowloon on 1932. Later, Beiping China Pencil Company and Shanghai China Pencil Factory were successively established, both of which were semi-finished products processing plants. From 65438 to 0934, China Standard Domestic Pencil Factory was established in Shanghai, and self-made lead cores were started to study domestic raw materials to make pencils. After the founding of New China, Harbin, Beijing, Tianjin, Jinan, Dalian, Fuzhou, Shenyang, Bengbu and other cities have successively built large pencil factories with an annual output of1.50 ~ 250 million. Lead core manufacturing, painting, printing and decoration techniques have also been continuously improved, and all-plastic pencils, resin fine lead cores and fine core movable pencils have been developed. New equipment such as rubber sheet binding dryer, automatic painting machine, electric tunnel core-burning furnace, grinding machine and various packaging machines have been developed.

[Edit this paragraph] Classification

Pencils can be divided into graphite pencils, colored pencils and special pencils according to their properties and uses.

assignee

Graphite pencil A pencil made of graphite as the main raw material. Can be used for drawing and general writing. Generally speaking, the hardness mark of graphite lead is H for hard pencil, B for soft pencil, HB for pencil with moderate hardness, and F for pencil with hardness between HB and H. Graphite pencils are divided into 6B, 5B, 4B, 3B, 2B, b, HB, f, h, 2H, 3H, 4H, 5H, 6H, 7H, 8H and 9h. The bigger the numbers before the letters, the harder or softer they are, respectively. In addition, there are 7B, 8B and 9B3 soft pencils to meet the special needs of painting. Colored pencils, colored pencil lead. The lead core consists of clay, pigment, talcum powder, adhesive, grease and wax. Used for marking symbols, painting, drawing charts and maps, etc. Colored pencils are usually packaged in sets (6 12, 24, 36, 64 colors). Special pencils include glass pencils, color-changing pencils, charcoal pencils, blueprint pencils, watercolor pencils and pastel pencils. They have their own special uses.

new technology

① Glass pencil: The lead core consists of pigment, grease and wax. Used for writing or marking on the surface of glass, metal, enamel, ceramics, leather, plastic, plexiglass, etc. , used by industry, medicine, national defense, measurement and other departments. There are red, white, orange, light yellow, purple, dark green, light blue, black and other colors. 2 color-changing pencil: commonly known as copying pencil. The lead core contains dyes such as sun-resistant purple lake, and the handwriting can't be erased with an eraser. It is suitable for writing long-term important documents and recording accounts. There are purple, red, blue, green, yellow and other colors, most of which are violet. 3 carbon pencil: also known as carbon pencil. The lead core is made of clay, charcoal powder, carbon black, etc. Used in painting and oil painting. 4 printing pencil: also known as tracing pencil. The graphite lead core is treated with oil-soluble wax red and other red dyes, which plays a shading role and is used to directly print the picture after drawing. ⑤ Watercolor pen: Acid dyes such as water-soluble acid scarlet are added to the lead core. Dipping lead in water is like watercolor paint, which is used for coloring photos, sketching, drawing maps, statistical charts and so on. ⑥ Pastel pencil: The lead core is made of pigment and porous and soft raw materials (such as calcium carbonate), and contains no grease or wax. Its hardness and writing feel are similar to chalk. Used for painting.

[Edit this paragraph] Raw materials

Pencil pencil raw materials mainly include pencil rod material, graphite lead core material, colored lead core material and appearance decoration material.

pen container

The main materials of pencil poles are wood and cement. When making a pen container from wood, it is required that the texture is upright, the structure is fine and uniform, the quality is soft or slightly soft, slightly brittle, contains less resin, has low hygroscopicity, swells and shrinks, and does not deform. There are mainly pencil cypress (red cypress), cedar, cedar, basswood, alder and so on. The adhesive should have proper viscosity, fluidity and wettability. The hardened adhesive layer has toughness, little damage to tools, certain water resistance, heat resistance and aging resistance, easy curing at room temperature, short curing time and no toxicity. There are mainly animal glue, polyester acid vinyl emulsion, hot melt adhesive and so on.

lead to

The raw materials and auxiliary materials of graphite lead core are graphite and clay. Graphite is used as a colorant. Using the lubricity and plasticity of lead core, you can draw black marks, stick them firmly on paper and erase them with rubber. Graphite with high carbon content and fine particles should be selected. Clay is a binder, and graphite particles are bonded together by its plasticity and cohesiveness. Clay with good plasticity, low iron content and wide sintering range is needed. Auxiliary materials include molding materials and materials that change the properties of lead cores. Molding materials are used to improve plasticity and adhesion, and improve the formability of lead cores. Commonly used are maltose, tragacanth and so on. The material that change that properties of the lead core are use for oil immersion treatment of the sintered lead core to improve the physical properties of the lead core (such as wear, concentration, stress at the core tip, smoothness, hardness, etc.). ). Commonly used are paraffin, cattle and sheep oil, vaseline, etc. , usually two or more are used together. The raw materials of colored lead core are pigment, physical raw materials, adhesive, grease and wax. Pigments (including pigments and dyes) play a coloring role, which requires good coloring power, high hiding power, soft texture, high fineness, good heat resistance and non-toxicity. Commonly used are titanium dioxide, carbon black, phthalocyanine blue and so on. Physical raw materials play the role of bonding, skeleton and hardness adjustment.

external

Exterior decoration materials mainly include nitrocellulose pencil paint, ink, electrochemical aluminum foil, rubber head, aluminum hoop and so on. The manufacturing process can be divided into pencil board, lead core, pencil rod, finished product decoration and other processes. In pencil board processing, logs are cut and chopped, sawed into wood blocks, and then cut into pencil boards with a cutting machine after hydrothermal treatment. The plate is 184mm long, 73mm wide and 4.8 ~ 5.2 mm thick. After heating (60 ~ 120℃) and drying at high temperature (130 ~ 200℃), the pencil board becomes soft and easy to roll. Lead core processing graphite lead core is prepared from graphite and clay according to a certain proportion, mixed by a kneader and a three-roller machine, extruded into a certain size lead core by a core pressing machine (for example, the lead core diameter of HB ~ 3h is 1.80 ~ 2. 10 mm), heated (50 ~ 150℃) and heated at high temperature (. The processing of colored lead core is similar to that of graphite lead core, but it does not need sintering. There are two processing methods: one is to mix clay, talcum powder, adhesive, pigment, grease and wax evenly, and then make it through molding and drying, which is called mixing method; The other is to mix porcelain clay, talcum powder, pigment and adhesive evenly and then squeeze them into lead core, or put the dried lead core into an oil core container to make it fully absorb oil at a certain temperature, which is called oil immersion method. The processing of the pencil rod is to plane the pencil board into a grooved board with a thickness of 4. 1 ~ 4.2 mm and a core groove corresponding to the diameter of the lead core. Then the lead core and pencil board are bonded together with adhesive, heated (50 ~ 120℃) and dried 1 ~ 8 hours in the clamped state, and then planed. The white pencil with decorative appearance is painted and printed, cut, printed with trademark and fitted with glue head, which makes it a finished pencil with certain specifications, appearance color and pattern.

[Edit this paragraph] category

annotate

Pencil These indicate the hardness of the pencil, which is determined according to the hardness of the refill. From soft to hard, they are 6b, 5b, 4b, 3b, 2b, b, HB, h, 2h, 3h, 4h, 5h, 6h b- black hardness h- hard. The more numbers of B, the darker and softer the pencil color, and the more numbers of H, the harder and lighter the color. HB is in the middle "B" is the initials of the English word "Black", which stands for the composition of graphite and the softness of pencil lead and the obvious degree of writing. The bigger the number in front, the darker the color.

Pencil lead resistance reference value

The following table lists the reference values (ohms) of different types of pencil lead resistors: model-resistance (ohms)-China 6B-3 China 5B-3.5 China 4B-4.5 China 3B-6 China 2B-9 China B- 0 China 3H-47 China 4H-59 China 5H-76 China 6h- 143 Most pencils are refilled with graphite, one of the allotropes of carbon. Pencils are classified according to the graphite content in the refill. Generally, it can be divided into three categories: H, HB and B. Among them, H-shaped pencils have higher hardness and are suitable for objects with relatively hard or rough interfaces, such as carpentry scribing and field drawing. HB pencil refill has moderate hardness and is generally suitable for writing. Class B pencils, with soft refills, are suitable for drawing, and can also be used to fill some cards that can be recognized by machines. For example, at present, we often use 2B pencil to fill in the answer sheet. In addition, colored pencils, usually called crayons, are often used for drawing. Many people may not know that pencils can also identify the authenticity of diamonds. After the diamond is wet with water, scrape it with a pencil, and the surface of the real diamond will not leave pencil marks. Fake diamonds made of crystal, glass, tourmaline, etc. It will leave a mark. [China Famous Brand] China Standard Domestic Pencil Factory Co., Ltd. (1954 renamed as China No.1 Pencil Factory, 1992 changed into China No.1 Pencil Co., Ltd.) was established in 1935, specializing in the production of wooden pencils of "China" and "Great Wall", which is one of the famous brands of Chinese pencils. Won many honorary titles, among which "Zhonghua Brand" D pencil won the only highest award in the national pencil industry "National Silver Award for Quality" and the national best-selling domestic product "Jinqiao Award", won the title of the only China brand in the national pencil industry in 2004, and won the only national inspection-free product in the national pencil industry in 2005. [20 things you don't know about pencils] 1. If you accidentally get stabbed by a pencil, you won't get lead poisoning, because pencils don't contain lead, but clay and graphite. Of course, if you stab someone, you may be charged with intentional injury ... 2. For those who like to review history and gossip, here is a joke about Watergate: Gordon Call described it in his autobiography. When he came to the office and saw John Dean, the sharpened pencil on the desk turned his head and stabbed him to death. Dean was a traitor to Ulundu in Watergate. Graphite, a carbon crystal discovered in Korsvik, England in the 6th century1named by A.G.Werner, a chemist in the 8th century/kloc-0, comes from the Greek graphein, which means "writing" 4, while -pencil-. Writing with a pencil is basically a manifestation that its fragments are stuck in the fibers of the paper. His fragments are not big,11000 inch. 6. Is it uncomfortable to be idle? It is said that an ordinary pen can draw a line 35 miles long or write 45,000 words (in western languages). Has anyone tested it? History proves that it is not. Comrades! The first chance in the world! ! 7. As early as the first century AD, Philip of Thessalonica, a Greek poet, used lead writing tools to write. However, the contemporary pencil was recorded by Swiss naturalist Conrad Gesner in 1565 (he died that year). 8. The French are the second generation parents of pencils (yes, without them, maybe the whole world would use brushes): 1795, Nicolas-Jacques Conte invented the manufacturing technology of clay graphite mixed materials. 1828, Bernard Lassimone invented the pencil sharpener (or pencil sharpener). 1847, Therry des Estwaux invented the automatic pencil sharpener. 9. French (you again! ) also make an eraser out of caoutchouc (a gum secreted by plants, which is said to be a combination of Spanish caucho and Tupi (a language from South America), so that the misspelled words can finally be wiped without crumbs. 10, basically all pencils sold in America have rubber heads, but those sold in Europe don't. Do Europeans make fewer mistakes in writing? ) 1 1, henry david thoreau, American writer, philosopher and pencil user. He wrote the famous essay Walden Lake with a pencil (I read it on Amazon, with more than 300 pages). In fact, he can use these pencils for free because his father runs a pencil factory in Boston. 12, 186 1 year, Abraham Faber established the first large pencil factory in the United States, which was located in new york. (In other words, Thoreau's father's pencil factory is at the local level) 13. During the civil war, the standard equipment of allied soldiers (northern bourgeoisie) included pencils. 14, 1822 invented mechanical pencil and set up a factory in Britain (it is estimated that the French invented it long ago, just because it was not romantic-_-), but the factory was bombed by Nazi Germany at 194 1 (probably hate pencils). 15, I am a red pencil. 19 17 After the Soviet Union seized power, American armand Hamel obtained the exclusive right to sell pencils in the Soviet Union. 16, China is, in a sense, the real parents of pencils now. In 2004, China made 654.38+000 billion pencils, which can basically circle the equator 40 times. 17. You can write with a pencil in weightlessness, so the pencil was taken into space. However, engineers from the National Aeronautics and Space Administration (NASA) said that in pure oxygen environment, wooden pencils may burn, and pencil scraps are even more dangerous. 18, and then Apollo 1 caught fire ... Later, a man named Paul Fisher invented the sealed pencil, so the pencil continued to serve the aviation industry. 19. The world's largest pencil pestle stood in front of the pencil factory in Kuala Lumpur, Malaysia, and let out a sigh. 20 meters high, composition: wood and polymer. On the other side of the world, engineers at the University of California use atomic force microscopes as pencils (! ! ! ) drew a line 50 nanometers wide. Taxpayer's money. [The Future of Pencil] Pencil is different from any tool or process we know so far, and the future of pencil may be the same as its past. Most of the instruments or mechanical devices we use now will undergo some form of improvement in the years to come. Pencils and books printed and bound in the traditional way may be extremely rare exceptions. Interestingly, these two things are easy to carry, which seems to be related to their popularity. Pencils can be put in any pocket, or even put on your ears smartly; A book, if the folio is small, can be stuffed into a man's trouser pocket or a woman's handbag. These two things can come in handy at any time, as long as users have enough imagination and alertness. Despite mechanical pencil, erasable pens and computers, ordinary pencils will still be with us. People can see the clue from the fact that the total annual sales of pencils in the world has reached 654.38+04 billion. Pencil has a very long history, which originated in ancient Greece and Rome more than 2000 years ago. At that time, the pencil was very simple, just a lead bar or even a lead block in the metal sleeve. But in a sense, it is a veritable "pencil." The pencils we use today are made of graphite and clay and contain no lead.