| 摘要 |
PURPOSE:To obtain a core for a writing utensil having high strength against folding by constituting the material quality of a pipe like molded product of a mixture of soft polyethylene and hard polyethylene and containing said soft polyethylene in an amount of 10wt.% or more. CONSTITUTION:A pipe like molded product is obtained by using a mixture of soft polyethylene and hard polyethylene and, as soft polyethylene, Sunteck, M2004, Ultozex, Patrosen, Haimiran, or the like are designated and, when the amount thereof is less than 10wt.%, no effect is obtained. As hard polyethylene, Sunteck, B870, nitrogen polyethylene, Novatec, Nipolon hard or the like are designated and, when the amount thereof is more than 90wt.%, buckling or cracking is generated when the molded product is folded at low temp. and no effect is obtained. As a result, a core for writing utensil having high strength against folding is obtained. |
