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K.RAGAVI,MCA Anna University, Chennai. PENCIL
19

Pencil invention

Feb 08, 2017

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Ragavi KN
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Page 1: Pencil invention

K.RAGAVI,MCAAnna University, Chennai.

PENCIL

Page 2: Pencil invention

AGENDAIntroductionHistory Of PencilConrad Gesner And His PencilNicholas Jacques ContePencil ManufacturingTypes Of PencilGrading And Classification Of PencilsConclusionReferences

Page 3: Pencil invention

INTRODUCTION

PENCIL:A pencil is a writing implement or art medium constructed of a narrow, solid pigment core inside a protective casing which prevents the core from being broken or leaving marks on the user’s hand during use.

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HISTORY OF PENCIL1564- This is where the story of the graphite

pencil begins.The first pencil was invented by “Conrad Gesner”.The Gesner pencil was called as “lead pencils”.This "Gesner pencil" has a special history because

some people believe it was used by Shakespeare.In Gesner pencil they use only pure graphite, so it

is very difficult to use, because the graphite was very soft

When people handle this pencil it will be broken.

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CONRAD GESNER AND HIS PENCIL

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HISTORY OF PENCIL In 1795, Nicholas-Jacques Conte of France discovered the process of mixing graphite with clay. This mixture was then placed in a kiln fire, which produced a superior writing material. After the kiln fire, strips were cut and placed into wood.

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Nicholas-Jacques Conte

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Pencil ManufacturingThe top sequence shows the old method that required pieces of graphite to be cut to size; the lower sequence is the new, current method using rods of graphite and clay.

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MANUFACTUREThe pencil is actually a mix of finely grinded graphite and

clay powders.Before the two substances are mixed, they are separately

cleaned and dried in a manner that creates large square cakes.

Once the cakes have fully dried, the graphite and the clay squares are mixed together using water.

The amount of clay and graphite decides the pencil hardness

And the amount of time spent on grinding the mixture determines the quality of the lead.

The mixture is then shaped, cut, and then tempered in a kiln.

The resulting strings are dipped in oil or molten wax, this final process used for smooth writing ability of the pencil.

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Types Of PencilBy marking material:-

Graphite pencilsSolid graphite pencilsCharcoal pencilsCarbon pencilsColored pencils, or pencil crayonsGrease pencilsWatercolor pencilsErasable color pencils

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SHAPE & SIZESHAPE:-

Triangular HexagonalRoundBendable (flexible plastic)

SIZE:-

Typical(19 cm[7.5inch])Biggest[(23 m) long]it is world record.

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BY MANUFACTUREMechanical Pencils

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Plastic Pencils

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Pop a Point Pencils

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ERASER ATTACHED PENCILSOn 30 March 1858, the first patent was introduced.

For attaching an eraser to the end of a pencil.

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Grading and Classification H ("hardness") B ("blackness")

 F ("fineness") The standard writing pencil is graded HB.

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CONCLUSIONPencils are so useful and so common in our

daily livesPencils truly are one of the greatest

technological inventions of all-time.One pencil has the potential to draw a line 35

miles long, write an average of 45,000 words, absorb 17 sharpening, delete its own errors.

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THANKYOU……