US 12,344,702 B2
Polyurethane for polishing layer, polishing layer, and polishing pad
Kiyofumi Kadowaki, Kurashiki (JP); Mitsuru Kato, Kurashiki (JP); Minori Takegoshi, Kurashiki (JP); Chihiro Okamoto, Kurashiki (JP); and Shinya Kato, Chiyoda-ku (JP)
Assigned to KURARAY CO., LTD., Kurashiki (JP)
Appl. No. 17/262,060
Filed by KURARAY CO., LTD., Kurashiki (JP)
PCT Filed Jul. 19, 2019, PCT No. PCT/JP2019/028384
§ 371(c)(1), (2) Date Jan. 21, 2021,
PCT Pub. No. WO2020/036038, PCT Pub. Date Feb. 20, 2020.
Claims priority of application No. 2018-152144 (JP), filed on Aug. 11, 2018.
Prior Publication US 2021/0309794 A1, Oct. 7, 2021
Int. Cl. C08G 18/76 (2006.01); B24B 37/22 (2012.01); B24B 37/24 (2012.01); C08G 18/32 (2006.01)
CPC C08G 18/7657 (2013.01) [B24B 37/22 (2013.01); B24B 37/24 (2013.01); C08G 18/3206 (2013.01)] 19 Claims
 
1. A polyurethane, consisting of:
a thermoplastic polyurethane that is a reaction product of a polyurethane raw material comprising a polymer diol, an organic diisocyanate, and a chain extender,
wherein the polymer diol has a number-average molecular weight of from 600 to 1200,
wherein the chain extender in the polyurethane raw material consists of
from 50 mass % to 100 mass % of a first chain extender which is a diol compound having a straight-chain carbon backbone with 7 to 12 carbon atoms, and
from 0 mass % to 50 mass % of a second chain extender which is a diol compound having a straight-chain carbon backbone having a number of carbon atoms which is selected from the group consisting of 3 carbon atoms, 4 carbon atoms, 5 carbon atoms, 6 carbon atoms, 16 carbon atoms, and 18 carbon atoms.