| 摘要 |
PROBLEM TO BE SOLVED: To provide a card made of a plant-based plastic whose difficulty in production is eliminated and which has durability to heat and humidity.SOLUTION: The card is produced by using a noncrystalline aromatic polyester sheet as a central layer, using the three-layer structural core sheets 10 on both surfaces of the sheet, laminating the transparent oversheets 21, 22 comprising a noncrystalline polyester resin on both outer surfaces of the core sheets 10 and heat-fusion-bonding between each sheet. The three-layer structural core sheet 10 is comprised of an intermediate layer 11, a surface layer 12 and a rear face layer 13, and each layer is composed of a lactic acid-based polymer, a noncrystalline aromatic polyester resin, a thermoplastic elastomer and an inorganic filler. Besides, the percentage of the noncrystalline aromatic polyester resin in the resin composition composing the surface and rear face layers is set to be higher than that of the aromatic polyester resin in the resin composition composing the intermediate layer. The lactic acid-based polymer is a plant-derived polymer. |
