| 摘要 |
The present invention provides a polypropylene film packaging material which is suitable for packaging rice roll, sandwich, etc. The transparency and the appearance are excellent. The smell from the film is seldom generated. Particularly the packaging material has high linearity in the tearing direction of the squeezing direction of resin in film manufacturing under heating environment, and has excellent tearing characteristic with low tearing strength. The packaging material made of polypropylene film is characterized in that the packaging material is a non-stretching film which comprises atleast two layers of a base layer and a surface layer and satisfies the following key points (1)-(3): (1) the base layer comprises 99-99.97% by mass of propylene homopolymer with melting point above 162 DEG C and 0.03-1% by mass of phosphate ester metal salt which is taken as the organic crystal nucleating agent, and has a thickness more than 10 mu m; (2) the surface layer is composed of propylene-alpha alkene copolymer with melting point lower than 155 DEG C and has a thickness more than 1 mu m; and (3) the thickness range of the base layer is more than 50% of the total thickness of the packaging material but is smaller than 98% of the total thickness. |
