| 摘要 |
PURPOSE:To improve an anti-scratching property of a film and enable it to be thermally bonded with a metal sheet by forming a compound film with a polyester layer having a specific value or less in the coefficient of dynamic friction with metal and a polyester layer having a melting point within the range of a specific temperature. CONSTITUTION:This compound film is formed of a polyester layer (A layer) having the coefficient of a dynamic friction of 0.45 or less between the film and the metal at 80 deg.C and a polyester layer (B layer) having melting point of 180-240 deg.C. In this way, an anti-scratching property of the A layer reaches a practicable level, and the B layer side can be thermally bonded with a metal sheet. In addition, the content of ethylene terephthalate ring trimer (oligometer) in the A layer is preferably to be 0.7wt.% or less relative to the total quantity of polyester. In a container made of a metal sheet laminated with such a polyester compound film, when a heat treatment is carried out after filling foodstuffs therein, the quantity of eluted oligomer is restricted. |
