Method for manufacturing laminate

A method for producing a laminate, comprising integrally molding in a mold cylindrical expanded thermoplastic resin beads A having a through-hole and an aspect ratio L/D of less than 2 and cylindrical expanded thermoplastic resin beads B having a through-hole and an aspect ratio L/D of less than 2, the method comprising:

• filling expanded beads A in the mold;
• filling expanded beads B in the mold;
• and
• integrally heating expanded beads A and expanded beads B by supplying a heating medium,
• wherein the laminate is a laminate in which an expanded beads molded article (a) composed of the expanded beads A and having interconnected voids and an expanded beads molded article (b) composed of the expanded beads B and having interconnected voids are integrally laminated,
• a difference [Pb−Pa] between a voidage (Pa) of the expanded beads molded article (a) and a voidage (Pb) of the expanded beads molded article (b) is 5% or more,
• the voidage (Pa) of the expanded beads molded article (a) is 20% or less, and
• the expanded beads A and the expanded beads B satisfy the following requirements (1) to (3):
• (1) a difference [dB−dA] between an average hole diameter dA of the through-holes of the expanded beads A and an average hole diameter dB of the through-holes of the expanded beads B is 0.3 mm or more and 2 mm or less;
• (2) the expanded beads B have an average outer diameter DB of 3.5 mm or more and 5 mm or less;
• (3) a difference [DB−DA] between an average outer diameter DA of the expanded beads A and an average outer diameter DB of the expanded beads B is −0.3 mm or more and 2 mm or less.