公开(公告)号：US12240956B2

公开(公告)日：2025-03-04

申请号：US17591725

申请日：2022-02-03

Applicant: JSP CORPORATION

Inventor： Takumi Sakamura ,  Hajime Ohta

IPC: C08J9/18 ,  B29C44/34 ,  C08J9/00 ,  C08J9/12 ,  B29K23/00

Abstract: An expanded bead having a tubular shape with a through hole and a method for producing the same are provided. The expanded bead includes a foamed core layer and a covering layer. A polyolefin-based resin included in the covering layer has a melting point lower than a melting point of a polypropylene-based resin included in the foamed core layer. An average hole diameter d of the through hole of the expanded bead is less than 1 mm, and a ratio d/D of the average hole diameter d to an average outer diameter D of the expanded bead is 0.4 or less. The polypropylene-based resin for the foamed core layer has a flexural modulus of 1,200 MPa or more and a melting point of 158° C. or lower.

公开(公告)号：US12202951B2

公开(公告)日：2025-01-21

申请号：US17617521

申请日：2020-04-02

Applicant: JSP CORPORATION

Inventor： Nobumasa Koshita ,  Hajime Ohta ,  Shota Takagi

IPC: C08J9/16 ,  C08J9/18 ,  C08J9/224 ,  C08J9/232

Abstract: A modified expanded bead that includes an expanded bead which includes a specific base polymer (β) and a coating layer which includes a specific base polymer (α). The coating layer covers at least part of an outer surface of the expanded bead. The melting point Tα of the base polymer (α) and the melting point Tβ of the base polymer (β) satisfy a relationship of 0≤Tα−Tβ≤20. When the modified expanded bead is cut into two halves along a cutting plane to form two half portions and thereafter one of the two half portions is cut along planes perpendicular to the cutting plane to form ten small pieces, outermost pieces among the ten small pieces have a xylene-insoluble content (B) which is less than a xylene-insoluble content (A) in the half portion and the xylene-insoluble content (A) is 10-80% by mass.

公开(公告)号：US11904579B2

公开(公告)日：2024-02-20

申请号：US17905890

申请日：2021-02-12

Applicant: JSP CORPORATION

Inventor： Takashi Oi ,  Hajime Ohta

IPC: B32B27/08 ,  B32B27/32

CPC classification number: B32B27/08 ,  B32B27/32 ,  B32B2250/02 ,  B32B2266/025 ,  B32B2553/00

Abstract: A molded article of polypropylene-based resin expanded beads, obtained by in-mold molding of the polypropylene-based resin expanded beads, each bead including: a core layer, in a foamed state, having a polypropylene-based resin; and a covering layer, which covers the core layer, having a polyethylene-based resin. A molded article magnification X [times] of the molded article is 55 times to 90 times, a value of a product X·σ50 of a 50% compressive stress σ50 [kPa] and the molded article magnification X is 6500 or more, and a 5% compressive stress σ5 of the expanded beads molded article is 5 kPa to 25 kPa.

公开(公告)号：US11732101B2

公开(公告)日：2023-08-22

申请号：US17790997

申请日：2021-01-21

Applicant: JSP CORPORATION

Inventor： Tomohito Shimada ,  Hajime Ohta

IPC: B32B27/16 ,  C08J9/224 ,  C08J9/16 ,  B32B1/00 ,  B32B5/18 ,  B32B27/06 ,  B32B27/32 ,  C08J9/228

CPC classification number: C08J9/16 ,  B32B1/00 ,  B32B5/18 ,  B32B27/065 ,  B32B27/32 ,  C08J9/224 ,  C08J9/228 ,  B32B2266/025 ,  B32B2307/72 ,  C08J2323/12 ,  C08J2423/12

Abstract: An expanded bead having a through hole and including a foamed core layer which defines the through hole therein and which is constituted of a resin composition containing two kinds of polypropylene-based resins having different melting points, and a cover layer covering the foamed core layer and constituted of a polyolefin-based resin. The expanded bead gives a DSC curve in which an endothermic peak intrinsic to the resin composition and another endothermic peak on a higher temperature side thereof appear in a specific heat of fusion ratio. Molded articles include a multiplicity of the expanded beads.