Pencil thereby pushing a new tip to the top. Invented by Harold Grossman for Empire Pencil Company in 1967 and subsequently improved upon by Arthur D. Little for Empire from 1969 through the early 1970s; the plastic pencil was commercialised by Empire as the "EPCON" Pencil. These pencils were co-extruded, extruding a plasticised graphite mix within a wood-composite core. Residual graphite from a pencil stick is not poisonous, and graphite is harmless if consumed. Although lead has not been used for writing since antiquity, lead poisoning from pencils was not uncommon. Until the middle of the 20th century the paint used
Negro (lead pencil) what they call Nero pencils, which are similar in composition. Prismacolor also manufactures a lead-based black pencil that is very close in composition. Negro (lead pencil) Negro is the name of an artist's drawing medium, consisting of black pencil lead often encased in a wooden or paper tool. Its history and uses are common knowledge among illustrators and historians interested in illustrative art. The word "Negro", translates to "black" in Spanish and Italian, and is a term commonly used to describe artists' media and pigments that are black or dark in color. Negro lead was originally composed of a mixture