US 11,904,578 B2
Stretchable film
Tatsuya Hirano, Osaka (JP); Takaaki Maeda, Osaka (JP); and Akihiro Tanaka, Osaka (JP)
Assigned to C.I. TAKIRON CORPORATION, Osaka (JP)
Appl. No. 17/615,806
Filed by C.I. TAKIRON Corporation, Osaka (JP)
PCT Filed Jun. 4, 2020, PCT No. PCT/JP2020/022079
§ 371(c)(1), (2) Date Dec. 1, 2021,
PCT Pub. No. WO2020/246536, PCT Pub. Date Dec. 10, 2020.
Claims priority of application No. 2019-106404 (JP), filed on Jun. 6, 2019.
Prior Publication US 2022/0324207 A1, Oct. 13, 2022
Int. Cl. B32B 27/08 (2006.01); B32B 27/20 (2006.01); B32B 27/32 (2006.01)
CPC B32B 27/08 (2013.01) [B32B 27/20 (2013.01); B32B 27/32 (2013.01); B32B 2250/03 (2013.01); B32B 2250/24 (2013.01); B32B 2264/104 (2013.01); B32B 2274/00 (2013.01); B32B 2307/306 (2013.01); B32B 2307/308 (2013.01); B32B 2307/51 (2013.01); B32B 2307/732 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A stretchable film comprising:
an elastomer layer; and
a surface layer provided on any one or both of a first surface and a second surface of the elastomer layer,
wherein the surface layer contains one or more polypropylene-based resins selected from the group consisting of block polypropylene, which is a copolymer with ethylene, and random polypropylene, which is a copolymer with ethylene, and calcium carbonate,
a content of the calcium carbonate in the surface layer is 10% to 75% by mass with respect to a total mass of the surface layer,
a thickness of the elastomer layer is 20 μm to 55 μm,
a thickness of the surface layer is 0.4 μm to 5.0 μm, and
a melting point of the polypropylene-based resin is equal to or higher than 135° C. and lower than 160° C.