Patent ID: 7707803
Filing Date: 2010-05-04
Classification: B32B,B65D,Y02A,Y02W,Y10T

Abstract:
1. A method for producing a biodegradable bag for packing a food, comprising: step 1: laminating a barrier layer-supporting substrate layer comprising a biodegradable polymer with a melting point of 150° C. or higher onto a paper substrate layer comprising a paper to obtain a laminated film having a structure of a paper substrate layer/barrier layer-supporting substrate layer; step 2: vapor-depositing a ceramic and/or a metal and thereby forming a barrier layer having an oxygen barrier property and a water barrier property onto said barrier layer-supporting substrate layer of the laminated film having the structure of said paper substrate layer/barrier layer-supporting substrate layer to obtain a laminated film having a structure of a paper substrate layer/barrier layer-supporting substrate layer/barrier layer; step 3: laminating a sealant layer comprising a biodegradable polymer with a melting point of 120° C. or below onto the barrier layer having the structure of said paper substrate layer/barrier layer-supporting substrate layer/barrier layer to obtain a laminated film having a structure of a paper substrate layer/barrier layer-supporting substrate layer/barrier layer/sealant layer; step 4: making tubular said laminated film having the structure of said paper substrate layer/barrier layer-supporting substrate layer/barrier layer/sealant layer with said sealant layer being inside to bring both back sides into contact with each other, and heat-sealing said back side with each other; step 5: introducing a food to the inside of said tubular laminated film; and step 6: heat-sealing both ends of said tubular laminated film containing the food.