Plastic pencils
AssigneeTeijin Limited
InventorsAtsuhiko Mukai, Yoshio Mori
Life of this patent
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Abstract
Plastic pencils comprising a writing core, a porous casing to enclose said writing core, and a coating which is coated on the surface of said porous casing, said casing being a homogeneous unitary mixture composed of 100 parts by weight of atactic polystyrene, 10-40 parts by weight of polyethylene, 10-55 parts by weight of glass fibers and the required amount of coloring agent and having sharpenability comparable to that of incense cedar and a flexural modulus in excess of 30,000 kg/cm.sup.2, and said coating being a homogeneous unitary mixture composed of 100 parts by weight of atactic polystyrene, 5-50 parts by weight of polyolefin and a required amount of a coloring agent.
Claims3
A plastic pencil comprising a writing core, a porous casing to enclose said writing core, and a coating which is coated on the surface of said porous casing, said casing being a homogeneous unitary mixture composed of 100 parts by weight of atactic polystyrene, 10-40 parts by weight of polyethylene, 10-55 parts by weight of glass fibers and the required amount of a coloring agent and having sharpenability comparable to that of incense cedar and a flexural modulus in excess of 30,000 kg/cm.sup.2, and said coating being a homogeneous unitary mixture composed of 100 parts by weight of atactic polystyrene, 5-50 parts by weight of polyolefin and a required amount of a coloring agent.
Dependencies are inferred from the claim text.