US 11,753,515 B2
Method for producing molded foam articles, and molded foam articles
Kazuhiro Komori, Katsuragi (JP); and Yusuke Aikyo, Tsukuba (JP)
Appl. No. 16/982,648
PCT Filed Mar. 27, 2019, PCT No. PCT/JP2019/013193
§ 371(c)(1), (2) Date Sep. 21, 2020,
PCT Pub. No. WO2019/189361, PCT Pub. Date Oct. 3, 2019.
Claims priority of application No. 2018-064240 (JP), filed on Mar. 29, 2018; and application No. 2018-098222 (JP), filed on May 22, 2018.
Prior Publication US 2021/0024716 A1, Jan. 28, 2021
Int. Cl. C08J 9/12 (2006.01); B29C 44/34 (2006.01); B29C 44/42 (2006.01); B29K 67/00 (2006.01); B29K 105/00 (2006.01)
CPC C08J 9/122 (2013.01) [B29C 44/3449 (2013.01); B29C 44/42 (2013.01); B29K 2067/00 (2013.01); B29K 2105/0079 (2013.01); C08J 2367/02 (2013.01); C08J 2467/02 (2013.01); C08J 2477/06 (2013.01)] 8 Claims
1. A method for producing molded foam articles that molds molded foam articles continuously, the method comprising continuously repeating step 1, step 2, step 3 and step 4 described below in this order, wherein
step 1 comprises melting a resin composition that includes a liquid crystal polyester,
step 2 comprises introducing, with an introduction device, a supercritical fluid that is unreactive, in a supercritical state, with the liquid crystal polyester, and is a gas at normal temperature and normal pressure, into the resin composition in an amount of at least 0.1 parts by mass but not more than 0.3 parts by mass per 100 parts by mass of the liquid crystal polyester to form a resin composition mixture, and then melt-kneading the resin composition mixture,
step 3 comprises injecting the melt-kneaded resin composition mixture containing the supercritical fluid into a mold, and
step 4 comprises conducting foaming by lowering at least one of a pressure and a temperature of the supercritical fluid contained in the resin composition mixture to a value below a critical point of the supercritical fluid; and
the method further comprises measuring an amount introduced of the supercritical fluid; and
performing feedback control of the amount introduced of the supercritical fluid based on a measurement result; and
the liquid crystal polyester has a melt tension at a temperature 20° C. higher than a flow start temperature of at least 5 mN but not more than 100 mN.