摘要 |
The laminated film of the present invention comprises: an outermost layer (A) comprising a polybutylene terephthalate homopolymer, a polybutylene terephthalate copolymer or a mixture of the polybutylene terephthalate homopolymer and the polybutylene terephthalate copolymer; and an innermost layer (B) comprising a heat-sealing resin, the outermost layer (A) having a shape factor of not less than 2.2, which shows a peak shape of Raman spectrum thereof and is represented by the following formula (1): Shape factor = La/Lb (1) wherein La and Lb represent peak widths being present on higher- and lower-frequency sides, respectively, relative to a perpendicular line drawn from a peak top to a base line formed by a tangent line taken before and after the peak based on carbonyl stretching vibration, and being taken along a horizontal line at a height corresponding to one half of an intensity of the peak. The laminated film is prevented from being curled upon heat-sealing.
|