US 11,701,803 B2
Polycarbonate sheet press-formed body production method
Atsuhiro Tokita, Osaka (JP); and Masato Takasaki, Osaka (JP)
Assigned to MITSUBISHI GAS CHEMICAL COMPANY, INC., Tokyo (JP); and MGC FILSHEET CO., LTD., Saitama (JP)
Appl. No. 17/283,100
Filed by MITSUBISHI GAS CHEMICAL COMPANY, INC., Tokyo (JP); and MGC FILSHEET CO., LTD., Saitama (JP)
PCT Filed Oct. 3, 2019, PCT No. PCT/JP2019/039082
§ 371(c)(1), (2) Date Apr. 6, 2021,
PCT Pub. No. WO2020/075619, PCT Pub. Date Apr. 16, 2020.
Claims priority of application No. 2018-192739 (JP), filed on Oct. 11, 2018.
Prior Publication US 2021/0339436 A1, Nov. 4, 2021
Int. Cl. B29C 43/00 (2006.01); B29C 43/36 (2006.01); B29C 43/52 (2006.01); B29K 25/00 (2006.01); B29K 33/00 (2006.01); B29K 69/00 (2006.01)
CPC B29C 43/003 (2013.01) [B29C 43/36 (2013.01); B29C 43/52 (2013.01); B29C 2043/3602 (2013.01); B29K 2025/08 (2013.01); B29K 2033/08 (2013.01); B29K 2069/00 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method for producing a press-molded body of a polycarbonate sheet including a resin layer (A) containing a polycarbonate resin as a main component, and a resin layer (B) containing a high hardness resin (B) as a main component and a hard coat layer (C) sequentially stacked on at least one surface of the resin layer (A), the method comprising:
pre-heating the polycarbonate sheet to a temperature in the range of a glass transition point of the resin layer (A)−45° C. or higher and the glass transition point or lower;
locating the pre-heated polycarbonate sheet between an upper die and a lower die of a metal mold, wherein a time period after the pre-heating of the polycarbonate sheet is finished until the polycarbonate sheet is located between the upper die and the lower die of the mold is 90 seconds or shorter; and
clamping the mold to press one of the upper die and the lower die to the other of the upper die and the lower die to obtain the press-molded body of the polycarbonate sheet, wherein the mold has a temperature that is the glass transition point of the resin layer (A) or lower.