The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 12, 2025
Filed:
Dec. 19, 2019
Toyobo Co., Ltd., Osaka, JP;
Kouji Yamada, Otsu, JP;
Kazuhito Horinouchi, Otsu, JP;
Mahiro Nakano, Inuyama, JP;
Toru Imai, Inuyama, JP;
TOYOBO CO., LTD., Osaka, JP;
Abstract
The invention provides a biaxially oriented polypropylene film, wherein a relationship between a loop stiffness stress (S [mN]) in a longitudinal direction and a thickness (t [μm]) satisfies the formula S≥0.00020×t, a relationship between a loop stiffness stress (S [mN]) in a width direction and the thickness (t [μm]) satisfies the formula S≥0.0010×t, and a heat shrinkage rate of the biaxially oriented polypropylene film at 150° C. is not higher than 10% in the longitudinal direction and not higher than 30% in the width direction, a heat shrinkage rate of the biaxially oriented polypropylene film at 120° C. is not higher than 2.0% in the longitudinal direction and not higher than 5.0% in the width direction, and the heat shrinkage rate at 120° C. in the longitudinal direction is lower than the heat shrinkage rate at 120° C. in the width direction.