PROBLEM TO BE SOLVED: To provide an improved agricultural cellular plastic sheet which includes three layers including a back film, a cap film, and a liner film, respectively, has a high heat-insulating performance, even when used in a state vertically hung, is hardly deteriorated, even when exposed to UV rays, and can resist to employment for long period. SOLUTION: A method for producing a cellular plastic sheet includes steps for molding a melt-extruded polyolefin film by a vacuum molding roll to obtain the cap film 2, melt-bonding a back film 1 to the cap film 2, and further melt-bonding a liner film 3 to the cap tops of the cap film. Therein, a vacuum molding roll whose one end is free from the row of molding cavities is used, and the end of the liner film 3 is melt-bonded to the melt-bonded portion of the cap film 2 and the back film 1 to form an edge side 4 wherein three films are integrated. A product having a high light diffuse transmittance can be obtained by selecting the cross-sectional shapes of the cap. COPYRIGHT: (C)2009,JPO&INPIT
