| 摘要 |
<p>A transparent polyester film for use in the lamination coating of metallic cans, substantially formed from a polyester composition prepared by homogeneously mixing: (A) 70-40 wt.% of a polyethylene terephthalate based on repeating ethylene terephthalate units and having a melting point of 250-262 °C, and (B) 30-60 wt.% of a polybutylene terephthalate based on repeating butylene therephthalate units and having a melting point of 215-225 °C. The film is characterized by: (i) having a crystallization temperature of 65-120 °C, (ii) having a secondary transition point of 40 °C or above, (iii) having a plane orientation coefficient of 2.12 to 0.19 and (iv) being substantially free from the occurrence of white spots even when treated with steam at 130 °C for 30 minutes after being laminated with a metallic sheet. This film does not form any white spot after retorting when used for the lamination coating of metallic cans.</p> |
