Idemitsu, Kosan Kabushiki-kaisha (idemitsu Kosan Co., Ltd.)

Takeshi Matsumoto

Masami Tomikawa

Hidehiko Kaji

Osamu Isogai

Norio Sugi

Shoichi Iwata

Atsuo Ikenaga

Pencils not requiring sharpening are produced by wrapping a thermoplastic resin sheet, which has been uniaxially stretched, around a core material so that a stretched direction of the sheet forms a spiral against the core material, whereby the sheet forms a holder for the pencil which may be stripped off to selectively expose the core material.

Pencils not requiring sharpening

A polyethylene composition consisting of: (A) a high density polyethylene with a viscosity-average molecular weight of 10 .times. 10.sup.4 to 20 .times. 10.sup.4, a number average molecular weight of 1 .times. 10.sup.4 or greater and a ratio between weight average molecular weight and number average molecular weight of 20 or less; (B) at least one inorganic calcium compound selected from a group consisting of calcium sulfite, calcium sulfate and calcium carbonate; and (C) a solid lubricant, if desired, the composition produces a film or sheet whose internal tearing resistance is high and equal in both longitudinal and lateral directions and the processibility of the resin composition may be extremely improved by incorporating as a fourth component, within a range of 1:5 to 5:1 in weight ratio with respect to the aforementioned high density polyethylene, a different high density polyethylene with a melt index of 0.1 to 1.0.

Polyethylene composition

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Chiba, Japan

Takeshi Matsumoto