| 摘要 |
PROBLEM TO BE SOLVED: To obtain a resin composition which can give a polypropylene film improved in low-temperature heat sealability, slipperiness, etc., without detriment to good rigidity, transparency, impact resistance, etc., inherent in a polypropylene film by blending a propylene random copolymer with a propylene polymer having a crystallization temperature higher than that of the random copolymer in a specified ratio. SOLUTION: This composition comprises 55-99 pts.wt. (A) propylene random copolymer comprising propylene and ethylene and/or 1-butene and 45-1 pt.wt. (B) propylene polymer having a crystallization temperature TCB ( deg.C) as measured with a differential scanning calorimeter higher than the crystallization temperature (TCA)> ( deg.C) of component A and satisfies the following requirements: Tc>=0.75×Tm-5 [wherein Tc (n) is the peak top temperature on the maximum temperature side in a crystallization curve measured with a differential scanning calorimeter, and Tm ( deg.C) is the peak top temperature on the minimum temperature side in a melting curve], and WO<=6 wt.% (wherein WO is the amount of an eluate in a temperature range of 0 deg.C or below in temperature-rising fractionation chromatography.
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