PURPOSE: To provide a polypropylene film having a high glass transtion temp. and excellent steam barrier properties and suitable for use in food packaging, by blending a petroleum resin or terpene resin contg. no polar group with polypropylene, and molding the mixture into a film.
CONSTITUTION: 30W100pts.wt. petroleum resin contg. no polar group such as hydroxyl or carboxyl group, such as cyclopentadiene resin obtd. using an unsaturated petroleum hydrocarbon as a starting material, or terpene resin contg. no polar group, such as hydrogenated β-pinene, is blended with 100pts.wt. polypropyelene. The mixture is molten by heating, discharged through the nozzle of an extruder and cast on a cooled drum to obtain the desired polypropylene film. The film has a glass transition temp. of 25W50°C and water vapor transmission rate of 0.9g/m2/day/100μm or below and is excellent in transparency, stretchability, moldability, etc.
TSUCHIYA KATSUHIRO
TANAKA SHIGERU
| JPS4999646A | 1974-09-20 | |||
| JPS4722449A | ||||
| JPS461279A | ||||
| JP41007958A | ||||
| JPS5825341A | 1983-02-15 | |||
| JPS58185635A | 1983-10-29 |
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