Title:
POLYESTER FILM, LAMINATE, AND PRODUCTION METHOD FOR POLYESTER FILM
Document Type and Number:
Japanese Patent JP2023038267
Kind Code:
A
Abstract:
To provide a polyester film which imparts extensibility to a metal foil by resin, thereby capable of suppressing breakage of the metal foil, delamination between the resin film and the metal foil, and occurrence of pinhole even under various conditions such as draw depth, pressure, velocity during cold forming and which is suitable for cold forming application.SOLUTION: There is provided a polyester film, in which about stresses at the time of 5% elongation and stresses at the time of 15% elongation in each of four directions of 45°, 90° and 135° in a clockwise direction to 0° being an arbitrary direction on a film surface, stresses (A) measured at tensile speed of 100 mm/min and stresses (B) measured at tensile speed of 1000 mm/min satisfy the following conditions (1) and (2). Condition (1): the stresses at the time of 5% elongation in each of four directions are 70 to 120 MPa together with the stresses (A) and the stresses (B), and a difference between both stresses in each of four directions [the stresses (A)-the stresses (B)] are 15 MPa or less. Condition (2): the stresses at the time of 15% elongation in each of four directions are 90 to 180 MPa together with the stresses (A) and the stresses (B), and a difference between both stresses in each of four directions [the stresses (A)-the stresses (B)] are 10 MPa or less.SELECTED DRAWING: None
Inventors:
Kenny Akamatsu
Takayoshi Okuzo
Takayoshi Okuzo
Application Number:
JP2023003427A
Publication Date:
March 16, 2023
Filing Date:
January 13, 2023
Export Citation:
Assignee:
UNITIKA LTD.
International Classes:
C08J5/18; B29C55/14; B29C55/16; B32B15/09
Attorney, Agent or Firm:
Morimoto International Patent Office