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The <includeonly>[[Ebonite]]</includeonly><noinclude>Ebonite</noinclude> (often called ''hard rubber'' or also ''vulcanite'' in some old advertisements) is a <includeonly>material</includeonly><noinclude>[[materials|material]]</noinclude> invented<ref>see the [http://it.wikipedia.org/wiki/Ebanite italian] and [http://en.wikipedia.org/wiki/Ebonite english] entries of Wikipedia, which, however, present some discrepancies, in particular on the attribution of the invention to O. Meyer and T. Hancock for the first and Charles Goodyear for the second.</ref> in 1843 and produced by a rubber vulcanization process in which the natural rubber is mixed with a variable percentage (from 20 to 50%) of sulfur, and hardened by keeping it at high temperature for a prolonged time (a few hours around 150°C). Hard rubber is generally produced in sheets, bars or slabs, which must be subsequently processed; in fact, it is not possible to make it with a mould.

The <includeonly>[[Ebonite]]</includeonly><noinclude>Ebonite</noinclude> (often called ''hard rubber'' or also ''vulcanite'' in some old advertisements) is a <includeonly>material</includeonly><noinclude>[[materials|material]]</noinclude> invented<ref>see the [http://it.wikipedia.org/wiki/Ebanite italian] and [http://en.wikipedia.org/wiki/Ebonite english] entries of Wikipedia, which, however, present some discrepancies, in particular on the attribution of the invention to O. Meyer and T. Hancock for the first and Charles Goodyear for the second.</ref> in 1843 and produced by a rubber vulcanization process in which the natural rubber is mixed with a variable percentage (from 20 to 50%) of sulfur, and hardened by keeping it at high temperature for a prolonged time (a few hours around 150°C). Hard rubber is generally produced in sheets, bars or slabs, which must be subsequently processed; in fact, it is not possible to make it with a mould.

Ebonite is a hard and brittle material, very resistant to corrosion by acids, and softens when heated. It is an excellent electrical insulator. It is easy to process and has been used both for the construction of objects and as an electrical insulator (use that still holds today). It owes its name<ref>the "ebonite" one, still beeing much more commonly called "hard rubber" as "ebonite" was a trade name.</ref> because it was initially used as a substitute for ebony. Its chemical resistance characteristics have seen it used for many years as an insulator, coating for corrosion-prone parts and as a battery case for cars.

Ebonite is a hard and brittle material, very resistant to corrosion by acids, and softens when heated. It is an excellent electrical insulator. It is easy to process and has been used both for the construction of objects and as an electrical insulator (use that still holds today). It owes its name<ref>the ''ebonite'' one, still beeing much more commonly called ''hard rubber'' as ''ebonite'' was a trade name.</ref> because it was initially used as a substitute for ebony. Its chemical resistance characteristics have seen it used for many years as an insulator, coating for corrosion-prone parts and as a battery case for cars.

Ebonite is the first material used for the production of fountain pens, in use since the first examples produced at the end of 1800. If even some objects considered as "precursors" of the fountain pen were made of metal, the first fountain pens were born substantially as a result of the invention of this material, which with its characteristics of ease of use, chemical inertia (and consequent resistance to corrosion), proved to be optimal for the construction of that "reservoir" of ink that was in fact the main component of the first fountain pens, and this also thanks to its characteristics of thermal insulation, which avoid the transmission of heat from the hand to the air of the reservoir, with a consequent increase in pressure and loss of ink.  

Ebonite is the first material used for the production of fountain pens, in use since the first examples produced at the end of 1800. If even some objects considered as "precursors" of the fountain pen were made of metal, the first fountain pens were born substantially as a result of the invention of this material, which with its characteristics of ease of use, chemical inertia (and consequent resistance to corrosion), proved to be optimal for the construction of that "reservoir" of ink that was in fact the main component of the first fountain pens, and this also thanks to its characteristics of thermal insulation, which avoid the transmission of heat from the hand to the air of the reservoir, with a consequent increase in pressure and loss of ink.