US 12,291,006 B2
Polymer film and uses of the same
Tzu-Jung Huang, Taipei (TW)
Assigned to CHANG CHUN PETROCHEMICAL CO., LTD., Taipei (TW)
Filed by Chang Chun Petrochemical Co., Ltd., Taipei (TW)
Filed on Jan. 12, 2024, as Appl. No. 18/411,858.
Claims priority of application No. 202311207195.2 (CN), filed on Sep. 19, 2023; and application No. 112135738 (TW), filed on Sep. 19, 2023.
Prior Publication US 2025/0091328 A1, Mar. 20, 2025
Int. Cl. B32B 17/10 (2006.01)
CPC B32B 17/10761 (2013.01) [B32B 17/10036 (2013.01); B32B 17/10605 (2013.01); B32B 17/10899 (2013.01); B32B 2250/03 (2013.01); B32B 2250/40 (2013.01); B32B 2331/04 (2013.01)] 17 Claims
 
1. A polymer film, which comprises a first portion and a second portion laminated with the first portion, the first portion and the second portion independently consist of one or more layers, wherein:
each layer of the first portion independently has a melt index ranging from 3.5 g/10 min to 10.0 g/10 min, and each layer of the second portion independently has a melt index lower than 3.5 g/10 min;
each layer of the first portion independently has a thickness ratio of its thickness to the total thickness of the first portion and the second portion and a product of its melt index and the thickness ratio, with the proviso that the sum of the product of each layer of the first portion ranges from 0.39 g/10 min to 2.50 g/10 min; and
each layer of the second portion independently has a thickness ratio of its thickness to the total thickness of the first portion and the second portion and a product of its melt index and the thickness ratio, with the proviso that the sum of the product of each layer of the second portion ranges from 1.10 g/10 min to 2.95 g/10 min,
wherein each layer of the first portion and each layer of the second portion independently comprise polyvinyl acetal,
wherein the melt index of each layer of the first portion and the melt index of each layer of the second portion are measured in accordance with ASTM D1238 under 190° C. and a loading of 2.16 kg.