Biaxially oriented polyester film, laminate, and packaging container

By controlling the molecular weight distribution of chemically recycled polyester films between 1.9% and 5.5% for low molecular weights, the films are strengthened against breakage and yellowing, facilitating the production of high-quality laminates and packaging containers.

JP7883206B2Active Publication Date: 2026-07-01TOYOBO CO LTD
View PDF 5 Cites 0 Cited by

Patent Information

Application Number
JP2023005829
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2023-01-18
Publication Date
2026-07-01
Estimated Expiration
2042-07-29

AI Technical Summary

Technical Problem

Biaxially oriented polyester films made from chemically recycled materials are prone to breakage during stretching and exhibit a yellowish tint due to high levels of low molecular weight components, which complicates their industrial application.

Method used

The films are formulated with chemically recycled polyester, limiting the area percentage of molecular weights below 1000 to between 1.9% and 5.5% to reduce breakage and yellowing, and incorporating a printed, sealant, or adhesive layer to enhance functionality.

Benefits of technology

The solution reduces environmental impact, minimizes film breakage, and decreases yellowing, enabling the production of high-quality laminates and packaging containers.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 0007883206000003
    Figure 0007883206000003
  • Figure 0007883206000004
    Figure 0007883206000004
  • Figure 0007883206000005
    Figure 0007883206000005
Patent Text Reader

Abstract

To provide: a biaxially oriented polyester film that can reduce environmental impact, can reduce a yellow tint, and can inhibit or reduce film rupture that may occur during drawing; a laminate comprising the biaxially oriented polyester film; and a packaging container comprising the laminate.SOLUTION: A biaxially oriented polyester film 8 contains a chemically recycled polyester. In a molecular weight distribution curve obtained by gel permeation chromatography of the biaxially oriented polyester film 8, the area ratio of a region having molecular weight of 1000 or less is from 1.9% to 5.5%, inclusive, of the total peak area. The chemically recycled polyester can reduce environmental impact. The area ratio being less than or equal to 5.5% can reduce a yellow tint. The area ratio being greater than or equal to 1.9% can prevent the stress during drawing in a manufacturing process (i.e., the drawing stress) from excessively increasing, and thus can inhibit or reduce film rupture that may occur during the drawing.SELECTED DRAWING: Figure 1
Need to check novelty before this filing date? Find Prior Art

Citation Information

Patent Citations

  • Steam iron

    JP1985036099A

  • Chemical recycle of polyethylene terephthalate waste

    JP2000169623A

  • Thermal decomposition of polyethylene terephthalate

    JP2000302707A

  • Printed resin film, laminate comprising said printed resin film, packaging container comprising said laminate, and laminate comprising polyester film, and packaging container comprising said laminate

    JP6984717B1

  • Biaxially-stretched polyester resin film and manufacturing method for same

    WO2021200754A1