Patent 9701098 was granted and assigned to JSP on July, 2017 by the United States Patent and Trademark Office.
A polyethylene-based resin foam sheet with density of 15 to 150 kg/m3, including a foam layer containing, as a base resin, polyethylene-based resin, and antistatic layer which is lamination bonded to at least one side of the foam layer containing a polymeric antistatic agent and, as base resin, polyethylene-based resin, wherein polymeric antistatic agent melting point of 125 to 140° C. and ratio of its partial heat of fusion in a region above melting point to its total heat of fusion of 40% or lower, wherein antistatic layer contains the polymeric antistatic agent of 45 to 300 parts by mass based on 100 parts by mass of the polyethylene-based resin constituting the antistatic layer, wherein antistatic layer has a weight of 1 to 50 g/m2, and antistatic layer shows initial electrostatic potential of 50 V or lower when a voltage of 10 kV is applied to a surface for 30 seconds.