Laminate film and method of producing the same

DETAILED DESCRIPTION It is an object of the present invention to provide a laminate film which has a flexibility so as to deform in accordance with the decrease of content in a container made of the laminate film thereby to maintain a constant dropping velocity of the content and which conforms to the standard of an extraction test for obtaining ultraviolet absorption spectrum for an infusion solution container, designated by Japan pharmaceutical codex.
It is another object of the present invention to provide a method of providing a laminate film in which each layer forming the laminate film is not deviated from each other during a laminating step to prevent generation of wrinkles on the laminate film by eliminating defects in workability of a heat adhesive resin layer.
According to a first aspect of this invention, there is provided a laminate film comprising a plurality of olefine type films not having a hydrolysis property, but a heat resistant property, and at least one heat resistant film, both surfaces of which have vapor deposition coats of aluminum oxide and which is disposed between the olefine type films so as to be joined therewith via heat adhesive layers.
According to a second aspect of this invention, there is provided a laminate film comprising a plurality of olefine type films not having a hydrolysis property, but a heat resistant property, and at least one heat resistant film, both surfaces of which have vapor deposition coats of aluminum oxide and which is disposed between the olefine type films so as to be joined thereto via co-extruded resin layers each comprising a heat adhesion resin layer and an olefine type resin layer.
In these laminate films according to the first and second aspects of this invention, the heat resistant film disposed intermediately between the olefine type films does not hydrolyze when it is dipped into hot water because an olefine type film with a heat resistant property and without a hydrolysis property is disposed on the outer surface side of a container and a vapor deposition coat of aluminum oxide is provided on each surface of the heat resistant film