Pencil invention

about pencils history

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

2. AGENDA Introduction History Of Pencil Conrad Gesner And His Pencil Nicholas Jacques Conte Pencil Manufacturing Types Of Pencil Grading And Classification Of Pencils Conclusion References

3. 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.

4. HISTORY OF PENCIL 1564- 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.

5. CONRAD GESNER AND HIS PENCIL

6. 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.

7. Nicholas-Jacques Conte

8. Pencil Manufacturing The 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.

9. MANUFACTURE The 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.

10. Types Of Pencil By marking material:- Graphite pencils Solid graphite pencils Charcoal pencils Carbon pencils Colored pencils, or pencil crayons Grease pencils Watercolor pencils Erasable color pencils

11. SHAPE & SIZE SHAPE:- Triangular Hexagonal Round Bendable (flexible plastic) SIZE:- Typical(19 cm[7.5inch]) Biggest[(23 m) long]it is world record.

12. BY MANUFACTURE Mechanical Pencils

13. Plastic Pencils

14. Pop a Point Pencils

15. ERASER ATTACHED PENCILS On 30 March 1858, the first patent was introduced. For attaching an eraser to the end of a pencil.

16. Grading and Classification   H  (" hardness" ) B  (" blackness ")   F  (" fineness ") The standard writing pencil is graded  HB .

17. CONCLUSION Pencils are so useful and so common in our daily lives Pencils 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.

18. REFERENCES https://pencils.com/the-story-of-pencils/ https://en.wikipedia.org/wiki/Pencil http://www.phy.mtu.edu/~jaszczak/borrowdale.html https://upload.wikimedia.org/wikipedia/commons/thumb/f/fa/PencilGradingChart.png/220px-PencilGradingChart.png https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcTz3zKIHp3DSXeufIxXdWoD_G2PnSb5N203bauf2eV5YPENwPEWEQ

19. THANKYOU……