POLYMETHYLPENTENE SHEET, FRESHNESS-RETAINING CONTAINER AND TRANSPORTATION METHOD OF PERISHABLES

摘要

PROBLEM TO BE SOLVED: To bring out the heat-sealing property of polyester resin, by using polymethylpentene sheet having a specified index showing the wettability of the surface. SOLUTION: This applied polymethylpentene is an independent polymer of poly 4-methylpentene-1 or a copolymer with otherα-olefin and produced to form sheets by an extruding method. The extruded sheet is applied with a corona discharge treatment to become 60-75 degrees in the contact angle measured with water of 25 deg.C. It is preferable to execute this treatment for only one side face. The polymethylpentene sheet processed in this treatment is used for the cover sheet 2. After perishables have been contained in the container body 1 with a flange 10 made of polyester resin, the flange 10 and the cover sheet 2 are sealed 3 together with heat. Then, it is used for transportation of perishables. In this way, the sealing material does not get out of place owing to vibration or the like during the transportation.