In antiquity, there were various ways to leave a trace on support. The best known is the reed cut (calm) used as pen and ink, many representations of scribes attest. The major disadvantage is to carry a vial that can break, spill and stain.
Another technique already is known Romans and mentioned by the Greek poet Philip of Thessaloniki II the century was to use lead crystal shaped style (plumbum).
In the Middle Ages, copyists use the pen, but from the XI the century, we begin to use the pencil lead for current writings.
Although widespread in XV the century, the graphite (1/3 2/3 tin and lead) will be definitively abandoned in the middle of XIX the century.
Around 1560, a very pure graphite mine was discovered in Borrowdale, Cumberland, England. This product, dirty to manipulate, is cut into a stick then surrounded by wood and takes the name of “plumbago” in English or plumbago in French, meaning “kind of lead.” (today the word “mine” of pencil, bears the name of “lead” in English, also meaningless). The description of the product, ancestor of the pen, appears in the fossil treaty of the Swiss naturalist Conrad Gesner written in 1565.
The city archives of Nuremberg report that in 1662 a craftsman named Friedrich Staedtler made pencils. His grandson, Johann Sebastian Staedtler founded a manufacturing plant in 1835. Pure graphite is expensive and rare (used in the shop), substitutes are sought.
From 1760 in Stein near Nuremberg, Kaspar Faber created a pencil manufacturing plant using graphite powder mixed with gums, resins, glue, sulfur, antimony and other substances, but none of these preparations gave pencils of identical quality to English pencils.
In 1779, the Swedish chemist Karl Wilhelm Scheele (1742-1786) discovered that plumbago is carbon.
The crystalline form of graphite is hexagonal with rhombohedral symmetry. It disintegrates into a sheet. Its hardness is low from 1 to 2 on the Mohs scale. Bold, it leaves a black line on vitrified porcelain. Its density is low, 2.26 g / cm 3. It is an excellent conductor of electricity and heat and has a high melting point, 3500 ° C. It is hugely acid resistant, chemically inert and highly refractory. Lightweight and resilient, it is incorporated as woven fibers in composite materials. The word graphite, from the Greek graphein, to write, will be given by in 1789 by the German geologist Abraham Gottlieb Werner (1750-1817).
In 1794, France was at war with England, country of manufacture of quality pencils. The Committee of Public Safety in the person of Carnot charges Nicolas Jacques Conte (1755-1805 ) to find a way to replace the pencils of England. Mixing clay with graphite, Conte obtains a paste that after extrusion and baking at over 1000 ° C gives the pencil lead. The patent is filed as early as 1795. The wood used to coat these pencils was linden and spruce for ordinary pencils, cedar for beautiful pencils.
In reality, the paper pencil was invented simultaneously by Conte and Joseph Hardtmuth, a porcelain manufacturer in Vienna who will create a factory in Budweis in Czechoslovakia. It is likely that they met.
Franz, the grandson of Joseph Hardtmuth, will paint his pencils in yellow to suggest the Orient (region of the best graphites) and will call his range “Koh-I-Noor” in 1890. This is the origin of the yellow color of most American pencils (75%).
In 1839, Lothar von Faber, grandson of Kaspar Faber, improves the mixing process of the components to have mine hardness as we know them today.
In 1843, William Brockedon patented a process to compress pure graphite powder, but the exhaustion of Borrowdale supplies halted production.
Table of Contents
The mine is an extruded mixture of clays, kaolin and bentonite (aluminum silicates), combined with graphite powder in a wet environment, then dried and finally fired at about 1200 ° C. The mines are stuck in the grooves of a wooden board, on which is glued another grooved wooden board. It only remains to cut the resulting board between two mines to obtain a pencil. Then come the finishes, be several layers of paint and inscriptions (brand, model, hardness …). Since 1858, Americans have systematically added an eraser to one end.
The range of pencils
The degree of hardness of a pencil depends on the clay/graphite ratio in the mine; the hardness increases with the proportion of clay. The clay content of a tight mine is of the order of 70%, whereas a very soft mine contains only about 30%. A scale allows characterizing the mine, which is either hard (H for hardness or hardness) is tender and fat (B blackness or darkness). An index placed in front of the letter indicates the degree. There are two intermediate values F for Fine point or end and HB. Some attribute the letter B to Bold or bold. Manufacturers like Staedtler have a set of grades E to 8E (extreme) mines extremely fat. There are also very hard HH and HHH grades. – This scale is not defined by any standard so that the hardness can vary according to the manufacturers. Americans have a similar size but with a different designation.
Which pencil to use?
The choice of a pencil depends on its field of use.
– artistic drawing: 3B at the 7B tender. For artists, there is have a watercolor pencil. You can read our Best Watercolor Pencils Review
– current use: B – 2B – HB – F medium
– technical drawing: H at 5H hard 6H at 9H extra hard
What name is given to this pencil?
– pencil 58%
– 24% paper pencil
– 12% wood pencil
– 6% lead pencil
Conte now produces some 750,000 wooden pencils a day. A regular pencil can draw a line about 55 kilometers long. Graphite comes mainly from Sri Lanka, Madagascar, Mexico and Siberia. The Sonora mine in Mexico produces an extremely dark powdery graphite.
This scale of hardness called “hardness pencil” is used to characterize paints, varnishes and coatings.
4H 5, 3H 4 1/2, 2H 4, H 3 1/2, F 3, HB 2 1/2, B 2, 2B 1 1/2, 3B 1, 4B 0
The hardness rating of a coating is the hardness of the hardest pencil that does not penetrate and scratches the coating. This scale of “scratch” hardness is analogous to the well- known Mohs hardness scale used in mineralogy. The technique consists of moving a cart containing a pencil on the surface to be tested, with a bearing force of 7.5 newtons at an angle of 45 ° (Standard ASTM D 3363). The determination of the hardness of a paint or varnish coating by the pencil hardness test is the subject of the ISO 15184 standard of 1998.
– Nicolas-Jacques Conté (1755-1805), an inventor of genius – From the pencils to the Egyptian expedition through the military aerostation … Alain Queruel, Ed L’Harmattan, 211p., 2004
Biography of Nicolas Jacques Conte
Nicolas-Jacques Conté was born August 4, 1755, in St-Cenery near Sees in Normandy and died in Paris December 6, 1805. He comes into the world in a family of modest peasants, becoming an orphan father very early. Very young, he shows tremendous manual skill, making a violin from 12 years. He decides to become a painter, but he has to cultivate the land to feed himself. He painted portraits and his reputation reached the ears of the bishop of Sees who ordered the execution of the paintings of the church (still visible today). Autodidact, Conte is passionate about physics and especially mechanics. He invents various machines among which one to raise the water. He gets married but miserable; the intendant of Alençon encourages him to try his luck in Paris. In 1785 he arrived in Paris. His activity of portrait painter allowing his household to subsist, he takes science classes. His technical skills and his attraction to chemistry made him meet physicist Charles, chemists Guyton de Morveau, Fourcroy and Vauquelin, mathematicians Vandermonde and Monge. The balloons allow to have a more precise vision of a battlefield, the Committee of Public Safety decides to create companies. In 1793, he was appointed a director of the national aerostation school in Meudon. During a gas chemistry experiment, an explosion takes his left eye. This wound is considered a feat of arms; he is appointed chief of a brigade of infantry, commander-in-chief of all the corps of balloonists. The Committee of Public Safety uses its knowledge to find a substitute for graphite pencils whose importation from England is under blockade. In 1794, he invented the pencil of paper that we use today whose mine is made of a mixture of graphite and clay. At the end of 1794, he was appointed demonstrator at the Conservatoire des Arts et Metiers. In 1796, Conté took part in the Egyptian expedition of Bonaparte as a lancer. He is also enrolled in the Science and Arts Commission. In 1798, the army lacked everything. Conte organizes mechanical workshops and will be appointed a director. From these workshops and foundries come various instruments and materials to meet the needs of the army: trumpets of cavalry, weapons, fabrics and uniforms, printing equipment, scientific instruments … even windmills. He is a member of the physics section of the Institute of Egypt since its creation in August 1798. He will be president in December 1800. His duties require him to stay in Cairo. In December 1799, he took part in the measurement of the height of the great pyramid of Cheops by measuring the variation of the atmospheric pressure using the barometer of his invention. He is interested in different Egyptian trades and paints workers and artisans at work in their workshops. Returning to France, he resumes his duties at the Conservatoire des Arts et Metiers. He was appointed in 1802 as Government Commissioner to the Commission to publish the Description of Egypt, chaired by Berthollet. He was awarded Knight of the Legion of Honor in 1803. Very tired and strongly affected by the almost simultaneous death of his brother and his wife, he died in Paris on December 6, 1805, he was only fifty years old. In St. Helena, Napoleon will say of him, “he was able to create the arts of France in the middle of the deserts of Arabia.”