MANUFACTURING METHOD OF BIODEGRADABLE AND DISPOSABLE NATURAL VESSEL USING CORN AND REDUCING PRODUCTION COST

摘要

PURPOSE: A manufacturing method of a biodegradable and disposable natural vessel is characterized by reusing waste corn or corn stems, being environment-friendly, reducing a production cost, increasing workability and mass-producing the vessel. A plastic vessel is replaced with the natural vessel. CONSTITUTION: A biodegradable and disposable natural vessel is obtained by the steps of: drying corn, corn stems and corn powder on under 13% of moisture content; grinding the dried materials with a grinder to make the material having 60mesh of size; putting the ground material into 4-8% of a dilute solution of sodium hydroxide to make the material have 8-9pH; cooking the material for over 1 hour to make pasty cellulose; mixing 30-50wt.% of corn starch and 50-30wt.% of calcium carbonate with a ribbon mixer for 30min. to make a mixture; kneading 40-60wt.% of the pasty cellulose and 60-40wt.% of the mixture with a kneader for 30min.-1hour; adding 40-50wt.% of hot water being 40-600deg.C, 3-5wt.% of glycerol, a softener, 3-5wt.% of gelatine, a connecting supplement and 2-3wt.% of sodium bicarbonate, a foaming agent, followed by agitating the mixture to make viscosity into 40000-80000cps; injecting the mixture into a metal mold; putting the injected mixture into a cylinder by compulsion; insulating thermally a material inputting path with flame retardant material having 5-15cm of thickness; pre-heating the agitated material at under 80deg.C with frictional heat of a screw and radiant heat of the mold; foaming and forming the vessel having 40-50wt.% of moisture content at 180-200deg.C at 80-100kgf/cm¬2 of pressure for 30-200sec.; falling the vessel with two-step motion of a metal cylinder; and then coating an inside of the vessel with an injecting method and a centrifugal method.