COMPOSITE BIAXIALLY ORIENTED POLYPROPYLENE FILM

• Main Authors: KANBE KEIICHI, ISHII KENTARO
• Format: Patent
• Language: English
• Published: 07.01.2000
• Edition: 7
• Subjects: LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; PERFORMING OPERATIONS; TRANSPORTING

PROBLEM TO BE SOLVED: To prevent occurrence of a curl without complicated work such as a reverse curl or the like and to upgrade gas shut-off properties by laminating ethylene-vinyl acetate copolymer saponified layers on both surfaces of a biaxially oriented film base layer containing polypropylene as a main body. SOLUTION: Ethylene-vinyl acetate copolymer saponified layers 12 are laminated on both surfaces of a base layer 11 to manufacture the composite biaxially oriented polypropylene film 10. The layer 11 is constituted by a resin containing polypropylene as a main body. As the layer 11, the sole polypropylene, a mixture of the polypropylene with a resin such as a propylene-ethylene copolymer or the like, blended with an antistatic agent, a defogging agent, an ultraviolet inhibitor and/or the like can be used. As the layer 12, a resin containing 25 to 60 mol.% of ethylene content and having 90% or more of a saponification degree is suitable. An adhesive layer 13 is arranged between the layer 11 and the layer 12 to improve an interlayer strength.