US 11,667,108 B2
Laminated steel plate, manufacturing method therefor, and sheet to be used therefor
Seokin Lee, Seoul (KR); Kweon Hyung Han, Gyeonggi-do (KR); and Kwangho Jang, Seoul (KR)
Assigned to SKC ECO-SOLUTIONS CO., LTD., Chungcheongbuk-do (KR)
Appl. No. 17/251,901
Filed by SKC ECO-SOLUTIONS CO., LTD., Chungcheongbuk-do (KR)
PCT Filed May 30, 2019, PCT No. PCT/KR2019/006481
§ 371(c)(1), (2) Date Dec. 14, 2020,
PCT Pub. No. WO2019/245184, PCT Pub. Date Dec. 26, 2019.
Claims priority of application No. 10-2018-0070767 (KR), filed on Jun. 20, 2018; and application No. 10-2019-0063082 (KR), filed on May 29, 2019.
Prior Publication US 2021/0122141 A1, Apr. 29, 2021
Int. Cl. B32B 15/09 (2006.01); B32B 15/01 (2006.01); B32B 15/082 (2006.01); B32B 15/085 (2006.01); B32B 27/08 (2006.01); B32B 27/30 (2006.01); B32B 33/00 (2006.01); B32B 37/12 (2006.01); B32B 37/15 (2006.01)
CPC B32B 15/09 (2013.01) [B32B 15/012 (2013.01); B32B 15/082 (2013.01); B32B 15/085 (2013.01); B32B 27/08 (2013.01); B32B 27/304 (2013.01); B32B 27/308 (2013.01); B32B 33/00 (2013.01); B32B 37/12 (2013.01); B32B 37/15 (2013.01); B32B 2250/03 (2013.01); B32B 2250/04 (2013.01); B32B 2250/05 (2013.01); B32B 2255/06 (2013.01); B32B 2255/26 (2013.01); B32B 2255/28 (2013.01); B32B 2307/538 (2013.01); B32B 2307/712 (2013.01); B32B 2307/714 (2013.01); B32B 2307/732 (2013.01); B32B 2311/24 (2013.01); B32B 2311/30 (2013.01); B32B 2323/00 (2013.01); B32B 2327/06 (2013.01); B32B 2327/12 (2013.01); B32B 2333/08 (2013.01); B32B 2367/00 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A laminated steel sheet, which comprises a steel sheet; and a first sheet disposed on the steel sheet, wherein the first sheet comprises an acrylic resin layer, and a fluorinated polymer resin layer formed directly on one side of the acrylic resin layer;
wherein the acrylic resin layer is a poly(methyl methacrylate) resin layer,
wherein the poly(methyl methacrylate) resin has a melt volume index (MVI) of 0.5 g/10 minutes to 10 g/10 minutes when measured at a temperature of 230° C. under a load of 3.8 kg,
wherein the fluorinated polymer resin layer is a polyvinylidene fluoride (PVdF) resin layer,
wherein the polyvinylidene fluoride resin has a viscosity in the range of 4,000 poise to 12,000 poise when measured at 230° C. at a shear rate of 100 s−1 using a rheometer,
wherein the first sheet is prepared by coextrusion,
wherein the acrylic resin layer and the fluorinated polymer resin layer have a surface roughness (Ra) of 0.01 μm to 2.0 μm, respectively, and
wherein the difference between the surface roughness (Ra) of the acrylic resin layer and the surface roughness (Ra) of the fluorinated polymer resin layer is 0.7 μm or less.