公开(公告)号：US20240025093A1

公开(公告)日：2024-01-25

申请号：US18217651

申请日：2023-07-03

Applicant: JSP CORPORATION

Inventor： Hisashi MASUMOTO

IPC: B29C44/44

CPC classification number: B29C44/445 ,  B29K2023/12

Abstract: An expanded bead of polypropylene-based resin formed with a through hole that is defined by an inner peripheral surface and that has an average hole diameter of 1 mm or less. The expanded bead has a closed cell content of 85% or more, an average cell diameter of 50 to 300 μm and an inner surface portion that extends along the inner peripheral surface that has an average cell diameter of 5 to 150 μm which is smaller than the average cell diameter of the expanded bead.