Method for producing polystyrene-based resin extruded foam plate, and polystyrene-based resin extruded foam plate

摘要

PROBLEM TO BE SOLVED: To provide a production method in which a polystyrene-based resin extrusion foamed board can stably be produced using a physical blowing agent containing hydro-fluoro-propene.SOLUTION: A polystyrene-based resin extrusion foamed board production method of the present invention is a method for producing a polystyrene-based resin foamed board having a low apparent density and a high extrusion direction vertical cross sectional area, and in which the physical blowing agent contains (A) saturated hydrocarbon and (B) hydro-fluoro-propene, the total addition amount of the physical blowing agent is in a particular amount, the addition amount of (A) saturated hydrocarbon is in a particular amount as well as the addition amount of (B) hydro-fluoro-propene is in a particular amount and the total addition amount of (A) saturated hydrocarbon and (B) hydro-fluoro-propene is in a particular amount, (B) hydro-fluoro-olefin contains (B1) 1,3,3,3-tetrafluoro-propene and (B2) 1-chloro-3,3,3-trifluoro-propene, and the mole ratio of (B1) and (B2) is in a particular range.SELECTED DRAWING: None