To provide a packaging material of high practical use which shows outstanding transparency, adhesive properties and superb gas barrier properties with the use of a polypropylene film base material and besides, is friendly to environments.
This packaging material comprises a transparent primer layer 2 consisting of a composite of a silane coupling agent, an acrylic polyol and an isocyanate compound, a vapor-deposited thin film layer 3 formed of an inorganic oxide with 5-100 nm thickness and a gas barrier composite coating 4 containing a water-based polymer, an inorganic laminar compound and a metallic alkoxide represented by the formula M(OR)n or a hydrolysate thereof, sequentially laminated on one of the faces of a polypropylene film base material 1. The interlayer distance of the inorganic laminar compound in the gas barrier composite coating 4 is extended 1.2 times or more, compared to the interlayer distance of the inorganic laminar compound before the formation of the composite coating 4.
KOMORI TSUNENORI
SEKIGUCHI MAMORU
