	US 12,460,027 B2
	Method for producing polyvinyl alcohol resin
Yoshihito Yamauchi, Tokyo (JP); and Norihito Sakai, Tokyo (JP)
Assigned to MITSUBISHI CHEMICAL CORPORATION, Tokyo (JP)
Filed by MITSUBISHI CHEMICAL CORPORATION, Tokyo (JP)
Filed on Sep. 7, 2022, as Appl. No. 17/939,418.
Application 17/939,418 is a continuation of application No. PCT/JP2021/013375, filed on Mar. 29, 2021.
Claims priority of application No. 2020-060379 (JP), filed on Mar. 30, 2020.
Prior Publication US 2023/0002519 A1, Jan. 5, 2023
Int. Cl. C08J 3/12 (2006.01); C08F 16/06 (2006.01)

CPC C08F 16/06 (2013.01)

3 Claims

1. A method for producing a polyvinyl alcohol resin having an absorbance of not less than 0.2 at 280 nm, the polyvinyl alcohol resin production method comprising:

melt-kneading a polyvinyl alcohol resin material and extruding a resulting melt into a polyvinyl alcohol resin sheet;

cooling the polyvinyl alcohol resin sheet; and

pulverizing the cooled polyvinyl alcohol resin sheet;

wherein the cooling the polyvinyl alcohol resin sheet comprises sandwiching the polyvinyl alcohol resin sheet between belt coolers for the cooling.