Title:
PROCESS FOR PRODUCING EXPANDED POLYETHYLENE-BASED RESIN BEADS AND PROCESS FOR PRODUCING POLYETHYLENE-BASED MOLDED RESIN OBJECT BY IN-MOLD FOAMING
Document Type and Number:
WIPO Patent Application WO/2017/169568
Kind Code:
A1
Abstract:
The present invention relates to a process for producing expanded polyethylene-based resin beads by expanding polyethylene-based resin particles that comprise a polyethylene-based resin as the base resin, characterized in that the polyethylene-based resin particles have a melting point of 105-125°C and, when examined for viscoelasticity at a temperature of 130°C and a frequency of 1.67 Hz, have a tanδ of 0.3-0.7 and a complex viscosity of 5,000-20,000 Pa·s. The process is further characterized by including a one-stage expansion step in which the polyethylene-based resin particles are dispersed in an aqueous dispersion medium inside a closed vessel, a blowing agent comprising carbon dioxide is added thereto, and the mixture is heated and pressurized and then discharged into a region having a pressure lower than the internal pressure of the closed vessel, the expansion ratio in the one-stage expansion step being 10-18.
Inventors:
HAYASE YUKI
YOSHIDA TORU
YOSHIDA TORU
Application Number:
PCT/JP2017/009012
Publication Date:
October 05, 2017
Filing Date:
March 07, 2017
Export Citation:
Assignee:
KANEKA CORP (JP)
International Classes:
C08J9/18; B29C44/00; C08J9/228; B29K23/00
Foreign References:
| JPS56151736A | 1981-11-24 | |||
| JPS4985158A | 1974-08-15 | |||
| JP2016017144A | 2016-02-01 | |||
| JPS6284853A | 1987-04-18 |
Other References:
See also references of EP 3438173A4
Attorney, Agent or Firm:
IKEUCHI SATO & PARTNER PATENT ATTORNEYS (JP)
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