US 12,258,457 B2
Heat-shrinkable polyester-based film
Shintaro Ishimaru, Tsuruga (JP); and Masayuki Haruta, Tsuruga (JP)
Assigned to TOYOBO CO., LTD., Osaka (JP)
Appl. No. 17/042,031
Filed by TOYOBO CO., LTD., Osaka (JP)
PCT Filed Mar. 25, 2019, PCT No. PCT/JP2019/012394
§ 371(c)(1), (2) Date Sep. 25, 2020,
PCT Pub. No. WO2019/188922, PCT Pub. Date Oct. 3, 2019.
Claims priority of application No. 2018-068388 (JP), filed on Mar. 30, 2018; and application No. 2018-068389 (JP), filed on Mar. 30, 2018.
Prior Publication US 2021/0024708 A1, Jan. 28, 2021
Int. Cl. C08J 5/18 (2006.01); C08L 67/02 (2006.01)
CPC C08J 5/18 (2013.01) [C08L 67/02 (2013.01); C08J 2367/02 (2013.01); C08J 2467/02 (2013.01)] 8 Claims
 
1. A heat-shrinkable polyester-based film wound into a film roll,
wherein the heat-shrinkable polyester-based film comprises
(a) 90 mol % or more of an ethylene terephthalate unit based on total ester units, and
(b) 0 mol % or more and 7 mol % or less of a sum of (i) amorphous alcohol component content based on total alcohol component content and (ii) amorphous acid component content based on total acid component content, and
(c) 5 mol % or less of 1,4-butanediol based on a sum of total alcohol component content and total acid component content,
wherein (A) at least a part of ethylene glycol and/or terephthalic acid constituting the ethylene terephthalate unit is derived from biomass resource and a degree of biomass of polyester constituting the film is from 5% to 100% or (B) 50 wt. % to 100 wt. % of total polyester in the heat-shrinkable polyester-based film is recycled from PET bottles,
wherein the heat-shrinkable polyester-based film satisfies the following requirements (1) to (5):
(1) heat-shrinkage ratio in a width direction measured by shrinking the film for 10 seconds in 90° C. hot water is 50% or more and 75% or less,
(2) heat-shrinkage ratio in a longitudinal direction measured by shrinking the film for 10 seconds in 90° C. hot water is −6% or more and 14% or less,
(3) heat-shrinkage ratio in the longitudinal direction measured by shrinking the film for 10 seconds in 70° C. hot water is −6% or more and 6% or less,
(4) irregularity of thickness in the width direction is 1% or more and 20% or less, and
(5) degree of crystallinity calculated from density is 1% or more and 15% or less, and wherein amorphous molecules are oriented in the width direction of the film roll.